# Squaring the circle of value.

Michela Barbot

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Michela Barbot. Squaring the circle of value.. Quaderni Storici, 2025, LIX (3). hal-05531671

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Michela Barbot

# Squaring the circle of value.

## The «just estimation» of things in early modern Italy

forthcoming in «Quaderni Storici», 2025

### 1. Introduction: observing estimation as a procedure

When it comes to analysing the logics of formation of the value of things, early modern historians tend to refer almost exclusively to the analytical categories developed by the Second (or Neo) Scholasticism. Faced with the transformations brought about by the emergence of commercial and financial capitalism in the 15th and 16th centuries, the theologians and jurists belonging to this school of thought – also known as «School of Salamanca»<fnref n="1" /> – formalised a set of definitions which, according to a widespread interpretation, created a universal economic lexicon and laid the foundations of the modern economic science<fnref n="2" />.

Among the main concepts forged by neo-scholastic authors is the notion of «just price», which they split into two main variants: the «legal» or «political» price and the «natural» or «vulgar» one<fnref n="3" />. The first category coincides with the price that political authorities (whether

<footnote n="1">¹ On the School of Salamanca and its members, see M. GRICE-HUTCHINSON, *The School of Salamanca. Readings in Spanish Monetary History*, 1544-1605, Oxford 1952; R. DE ROOVER, *La pensée économique des Scolastiques. Doctrines et méthodes*, Montreal-Paris 1971; P. J. BARRIENTOS GARCIA, *Repertorio de moral económica (1526-1670): la Escuela de Salamanca y su proyección*, Pamplona 2011; J. M. BENEYTO, J. C. VARELA (eds), *At the Origins of Modernity. Francisco de Vitoria and the Discovery of International Law*, Cham 2017; W. DECOCK, *Theologians and Contract Law: The Moral Transformation of the Ius commune (ca. 1500-1650)*, Leiden-Boston 2013.</footnote>

<footnote n="2">² Thus J. A. SCHUMPETER, *History of Economic Analysis, from Antiquity until the middle of the twentieth century*, New York 1954; R. DE ROOVER, *Scholastic Economics: Survival and Lasting Influence from the Sixteenth Century to Adam Smith*, in «The Quarterly Journal of Economics», LXIX (1955), pp. 161-190; ID., DE ROOVER, *La pensée économique des Scolastiques*, cit.</footnote>

<footnote n="3">³ On these categories, largely inspired by the First Scholasticism, see M. MARTINAT, *Chi sa quale prezzo è giusto? Moralisti a confronto sulla stima dei beni in età moderna*, in «Quaderni Storici», 135 (2010), pp. 825-856; R. FRIGENI, *Una questione di ‘stima’. Tra prima e seconda Scolastica: dialettiche medievali e moderne intorno a valore e giusto prezzo*, in M. BARBOT, M. CATTINI, M. DI TULLIO, L. MOCARELLI (eds), *Stimare il valore dei beni. Una prospettiva europea (XV-XX secoli)*, Udine 2018, pp. 17-40; C. LENOBLE, *Iustum Pretium, justice sociale, lois du marché et croissance: histoire de sous-entendus*, in V. CHANKOWSKI, C. LENOBLE, J. MAUCOURANT (eds), *Les infortunes du juste prix. Marchés, justice sociale et bien commun de l’antiquité à nos jours*, Lormont 2020, pp. 74-100.</footnote>
local or central) impose with moral purposes<fnref n="4" /> on goods and commodities that are considered as
basic necessities<fnref n="5" />, while the second corresponds to the price of any type of thing whose
exchange does not require public pricing. Where the legal price is fixed, the natural price may
fluctuate within a variable range (or «latitude», *latitudo*) depending on time and space. To
clarify how this range is defined, the members of the School of Salamanca refer to the concept
of *communis æstimatio*: the extremes within which natural prices can vary are to be considered
as «just» only when they are established *communiter*, by the community as a whole<fnref n="6" />.

Since the beginning of the 20th century, the notion of *communis æstimatio* has given rise to
a sharp historiographical controversy, which remains partially unresolved to this day.

According to a first interpretation, which was initially prevalent but gradually became less
widely accepted, by using this expression, neo-scholastic authors intend to affirm the
imperative of guaranteeing individuals and their families a standard of living consistent with
their position in the social hierarchy<fnref n="7" />. This first meaning of *communis æstimatio* would
essentially place the natural just price within the sphere of distributive justice. Following
Aristotle and St Thomas Aquinas, the canonists of the School of Salamanca define this form of
justice as the principle that regulates relations between the political community and its members
in a proportional manner. The proportionality of this form of justice consists in distributing

<footnote n="4">⁴ The adjective «moral» refers here to the notion of «moral economy», as it is defined by E. P. THOMPSON, *The Moral Economy of the English Crowd in the Eighteenth Century*, in «Past & Present», 50 (1971), pp. 76-136.</footnote>

<footnote n="5">⁵ Although the meaning and range of basic necessities vary considerably in the time and space, this concept generally includes wheat and bread, as shown by J.-M. TUFFERY, *Ébauche d'un droit de la consommation. La protection du chaland sur les marchés toulousains aux XVIIᵉ et XVIIIᵉ siècles*, Paris 1998; M. MARTINAT, *Le juste marché: le système annonnaire romain au XVIᵉ et XVIIᵉ siècles*, Rome 2004; M. MARGAIRAZ, PH. MINARD, *Marché des subsistances et économie morale: ce que taxer veut dire*, in «Annales historiques de la Révolution française», 352 (2008), pp. 53-99; L. PARZIALE, *Nutrire la città. Produzione e commercio alimentare a Milano tra Cinque e Seicento*, Milan 2009; L. MOCARELLI (ed), *Quando manca il pane. Origini e cause della scarsità delle risorse alimentari in età moderna e contemporanea*, Bologna 2013; A. CLEMENTE, S. RUSSO (eds), *La polizia de' grani. Mercati, regole e crisi di sussistenza nelle economie di Antico Regime*, Soveria Mannelli 2019.</footnote>

<footnote n="6">⁶ According to Raymond de Roover (*The Concept of the Just Price: Theory and Economic Policy*, in «The Journal of Economic History», 18/4 (1958), pp. 418-434, p. 419), this adverb already appears in Accursio's Glosa, but this interpretation is rejected by G. TODESCHINI, *Ricchezza francescana: dalla povertà volontaria alla società di mercato*, Bologna 2004.</footnote>

<footnote n="7">⁷ Among the studies that share this interpretation are, for example, A. TARDE, *L'idée du juste prix, essai de psychologie économique*, Paris 1907; G. BARBIERI, *L'ordine economico nei pensatori ecclesiastici dell'epoca moderna*, Bari 1961; A. FANFANI, *Capitalismo, socialità, partecipazione*, Milan 1979; P. PRODI, *Settimo non rubare. Furto e mercato nella storia*, Bologna 2009, and F. MONSALVE, *Economics and ethics: Juan de Lugo's theory of the just price, or the responsibility of living in society*, in «History of Political Economy», 42 (2010), pp. 495-519. A similar view is also shared by recent economic studies inspired by Thomist thought, such as S. FREMEAUX, CH. N. LEMAITRE, *Qu'est-ce qu'une juste rémunération? Ce que nous enseigne la conception du juste salaire de Thomas d'Aquin*, in «Management & Avenir», 48/8 (2011), pp. 76-93.</footnote>
merits and resources according to each person's condition, with the dual objective of mitigating any threat to the stability of the social order and protecting those that are most at risk of exclusion<fnref n="8" />.

This former interpretation is, however, rejected by Joseph A. Schumpeter, Raymond de Roover and other authors who, drawing more or less explicit parallels with Adam Smith's theory of the invisible hand, argue that the natural just price enunciated by the school of Salamanca falls within the field of commutative or contractual justice<fnref n="9" />. Unlike distributive justice, which takes into account the «quality of persons» and their social position, commutative justice presupposes an arithmetic equivalence between the nature of the things exchanged, regardless of the identity of the participants in the exchange<fnref n="10" />. According to this second interpretation, the natural just price should be understood as the result of a series of completely mutual and symmetrical bilateral negotiations, and the *communis æstimatio* would represent a metaphor of the law of supply and demand in a perfectly competitive market<fnref n="11" />.

A third way of understanding the *communis æstimatio*, much less explored than the previous two, consists in analysing it as a procedure, intended in its dual etymological meaning: the generic sense of «a way of proceeding and operating to achieve a result» and the legal sense of «a set of formalities to be observed in the conduct of a trial»<fnref n="12" />. The relevance of this latter

<footnote n="8">⁸ On this concept of justice, developed by Aristotle in Nicomachean Ethics, see J. SOUDEK, *Aristotle's theory of exchange: an inquiry into the origins of economic analysis*, in «Proceedings of the American Philosophical Society», 96 (1952), pp. 45-75; A. LAPIDUS, *Le détour de valeur*, Paris 1986; E. GARIN, *La giustizia*, Naples 2003; P. JORION, *Le prix*, Paris 2010. In Old Regime societies, this form of justice is mainly intended for the «deserving» or «respectable» poors, as it is shown by G. RICCI, *Povertà, vergogna, superbia. I declassati fra Medioevo e Età moderna*, Bologna 1996; S. CERUTTI *Giustizia sommaria. Pratiche e ideali di giustizia in una società di Ancien Régime* (Torino XVIII secolo), Milan 2003, pp. 40-41; M. BARBOT, J.-F. CHAUVARD, S. LEVATI (eds), *L'expérience du déclassement social (France-Italie, XVIᵉ-premier XIXᵉ siècle)*, Rome 2021; S. CERUTTI, M. VALLERANI (eds), *Poveri*, special issue of «Quaderni Storici», 2 (2024).</footnote>

<footnote n="9">⁹ In addition to Schumpeter's work, see R. DE ROOVER, *La pensée économique des Scolastiques*, cit.; Id., *Monopoly Theory Prior to Adam Smith. A Revision*, in «The Quarterly Journal of Economics», 65 (1951), pp. 492-524; T. HUTCHINSON, *Before Adam Smith. The Emergence of Political Economy, 1662-1776*, Oxford 1996; W. DECOCK, *Le marché du mérite: penser le droit et l'économie avec Léonard Lessius*, Paris 2019.</footnote>

<footnote n="10">¹⁰ See, in this regard, J. J. SPENGLER, *Hierarchy vs Equality: persisting conflict*, in «Kyklos», 21 (1968), pp. 217-238; L. DUMONT, *Homo æqualis I. Genèse et épanouissement de l'idéologie économique*, Paris 1977; K. PŘIBRAM, *A History of Economic Reasoning*, Baltimore 1983.</footnote>

<footnote n="11">¹¹ R. DE ROOVER, *The Concept of the Just Price: Theory and Economic Policy*, in «The Journal of Economic History», 18/4 (1958), pp. 418-434; Id., *La pensée économique des Scolastiques*, cit.</footnote>

<footnote n="12">¹² https://www.treccani.it/vocabolario/procedura/. On the legal meaning of the notion of procedure, see R. AGO, S. CERUTTI (eds), *Procedure di giustizia*, special issue of «Quaderni storici», 101 (1999); A. D. KESSLER, *The Political Functions of (Premodern) Courts and Procedure and Questions of Comparative Method*, in «Law and History Review», 37-4 (2019), pp. 937-946.</footnote>
definition had already been mentioned by legal historian Yan Thomas (2002)<fnref n="13" />, who underlined
that economic valuation must also, and above all, be considered in light of its links with the
judicial sphere and contract law, of which price is one of the essential elements<fnref n="14" />.

In the wake of this third still little-explored research perspective, this article aims to inquire
on the procedural dimensions of estimation in the two senses mentioned above. Drawing on the
analysis of a series of manuals and appraisal reports drawn up in Milan and other Italian
contexts in the 17th and 18th centuries<fnref n="15" />, this investigation also sheds light on the methods and
criteria used to calculate a quantity called «intrinsic value», whose widespread use during the
preindustrial times has been well documented<fnref n="16" />, but not yet fully explained.

## 2. Estimation procedures and the ambition to articulate two forms of justice

Before presenting the main results of this research, it is worth noting that in early modern
Italy appraisal procedures are applied in a very large range of situations: tax levies,

<footnote n="13">¹³ Y. THOMAS, *La valeur des choses. Le droit romain hors la religion*, in «Annales. Histoire, Sciences Sociales», 57 (2002), pp. 1431-1462. The procedural dimension of estimations is also evoked by A. STANZIANI, *Rules of Exchange. French Capitalism in Comparative Perspective. Early Eighteenth to Twentieth Century*, Cambridge, 2012, pp. 20-21; M. BARBOT, *Le procedure di stima e la certezza dei prezzi* (Italia e Francia, secoli XVII-XVIII), in M. VALLERANI (ed), *Valore delle cose e valore delle persone. Dall'Antichità all'Età moderna*, Rome 2018, pp. 295-310; J-Y. GRENIER, *L'économie politique du juste prix* (de la Grèce ancienne au XXIᵉ siècle), in CHANKOWSKI, LENOBLE, MAUCOURANT (eds), *Les infortunes du juste prix*, cit., p. 183-207.</footnote>

<footnote n="14">¹⁴ M. BARBOT, 'Precium indicat contractum'. *I prezzi delle cose e il diritto civile* (Italia e Francia, XVII secolo), in F. AMMANNATI (ed), *I prezzi delle cose in età preindustriale*, Florence 2016, pp. 259-275; EAD., *Les règles de la valeur. Les prix et l'estimation au prisme du droit (XVIIᵉ-XVIIIᵉ siècle)*, Toulouse 2025.</footnote>

<footnote n="15">¹⁵ The examples and historical sources on the Milanese case are taken from a series of personal works that will be progressively quoted.</footnote>

<footnote n="16">¹⁶ B. DE MUNCK, *Guilds, product quality and intrinsic value. Towards a history of conventions?*, in «Historical Social Research/Historische Sozialforschung», 36 (2011), pp. 103-124; B. DE MUNCK, D. LYNA (eds), *Concepts of Value in Material Culture, 1500-1900*, Cornwall 2015 (especially pp. 133-149), and, for the medieval and Renaissance Italy, G. TODESCHINI, *Seconda mano. Il valore delle cose fra medioevo ed età moderna*, Rome 2025.</footnote>
confiscations, bankruptcies, dowries and inheritance transfers, transactions, dations in payment (or «datio in solutum»)<fnref n="17" />, and sales of a certain significance (economic or symbolic)<fnref n="18" />.

In all these situations, the valuation is generally carried out by sworn experts known as «periti stimatori». These experts can be either civil servants or artisans and merchants specializing in a particular economic sector<fnref n="19" />.

Although the rules for being designated as a «perito stimatore» varies from one jurisdiction to another, the formal conditions most often imposed by urban and regional legislations for holding this position include the possession of the status of citizen, the proof of «good faith and honesty» and the absence of physical impairments that could hinder sight, hearing or mobility<fnref n="20" />.

The latter requirement is justified by the quantity of physical actions (touching, seeing, walking, listening) that experts have to perform in order to carry out their tasks<fnref n="21" />. In addition to these conditions, the assessment of the «periti stimatori» must be made in the presence of witnesses,

<footnote n="17">¹⁷ The transaction (in Italian, «transazione», or «alienazione causa transactionis») is a contract seeking to avoid or settle a dispute between two parties, whereas the dation in payment, or datio in solutum, is a procedure that allows a debtor to discharge his obligation by transferring one or more assets to the creditor instead of the amount initially owed. In this regard, see respectively S. PARINI VINCENTI, *Tra tutto e niente. Studi sulla transazione civile dal XVII secolo al codice del 1865*, Milan 2018; G. ASTUTI, *Dazione in pagamento (storia)*, in *Enciclopedia del diritto*, v. XI, Milan 1962, pp. 727-733, V. Zafarana, *Datio in solutum, prospettive storico-comparatistiche*, in «Diritto & Diritti - Rivista giuridica elettronica», on line (2011); A. MONTI, *L'intervento 'pubblico' nei rapporti contrattuali privati e la stima dei beni. La prassi lombarda della datio in solutum (secoli XVI-XVII)*, in BARBOT, CATTINI, DI TULLIO, MOCARELLI (eds), *Stimare il valore dei beni*, cit., pp. 67-80; M. BARBOT, *Cedere aliud al posto del denaro dovuto. La datio in solutum fra teoria e prassi giudiziaria (Italia e Francia, XVII-XVIII secc.)*, in A. ORLANDI (ed), *Mezzi di scambio non monetari. Merci e servizi come monete alternative nelle economie dei secoli XIII-XVIII*, Florence 2024, pp. 259-274.</footnote>

<footnote n="18">¹⁸ Among the works that analyse appraisals in these different situations, cf. J.-Y. GRENIER, *L'économie d'Ancien Régime. Un monde d'échange et d'incertitude*, Paris 1996; R. AGO, *Economia barocca: mercato e istituzioni nella Roma del Seicento*, Rome 1998; G. ALFANI, M. BARBOT (eds), *Ricchezza, valore, proprietà in età preindustriale, 1400-1850*, Venice 2009; M. BARBOT, J.-F. CHAUVARD, L. MOCARELLI (eds), *Questioni di stima, special issue of «Quaderni Storici», 135 (2010); J.-F. CHAUVARD, A. BELLAVITIS, P. LANARO (eds), *Fidéicommis. Procédés juridiques et pratiques sociales (Italie-Europe, Bas Moyen Âge-XVIIIe siècle)*, in 'Mélanges de l'École Française de Rome. Italie et Méditerranée', 124-2 (2012); BARBOT, CATTINI, DI TULLIO, MOCARELLI (eds), *Stimare il valore dei beni*, cit.; G. ALFANI, M. DI TULLIO, *The Lion's Share. Inequality and the Rise of the Fiscal State in Preindustrial Europe*, Cambridge 2019; A. BUONO, L. GABBIANI (eds), *Sous tutelle. Biens sans maître et successions vacantes dans une perspective comparative, XIIIe-XXe siècles*, Paris 2020; BARBOT, *Cedere aliud al posto del denaro dovuto*, cit.</footnote>

<footnote n="19">¹⁹ On the figure of *perito stimatore*, see L. SICILIANO VILLANUEVA, *Estimatori, stimatori [storia del diritto]*, in *Il Digesto Italiano. Enciclopedia metodica e alfabetica di legislazione, dottrina e giurisprudenza compilata da eminenti giuristi italiani*, vol. XIV, Turin 1895-1898, pp. 1104-1105, but see also D. A. AZUNI, *Perito od esperto*, in ID., *Dizionario universale ragionato della giurisprudenza mercantile*, Nice, Société typographique niçoise, 1786-1788, pp. 275-276.</footnote>

<footnote n="20">²⁰ SICILIANO VILLANUEVA, *Estimatori, stimatori*, cit., p. 1104.</footnote>

<footnote n="21">²¹ The materiality of the actions performed by experts clearly emerge in the practice of tracing jurisdictional boundaries, as it is shown by A. STOPANI, *La memoria dei confini. Giurisdizione e diriti comunitari in Toscana (XVI - XVIII secolo)*, in «Quaderni Storici», 1 (2005), pp. 73-96.</footnote>
recorded in writing and carried out through technical tools and units of measurement officially approved by local authorities<fnref n="22" />. This set of requirements responds also to strict legal imperatives, since in many jurisdictions – as for instance in the State of Milan – estimation has the dual status of certification instrument and judicial proof<fnref n="23" />. This circumstance, in turn, means that experts often interact with the two main legal procedures applied in early modern courts: the ordinary procedure («procedura ordinaria»)<fnref n="24" />, mainly used by civil courts, and the summary procedure («procedura sommaria»), typical of special and commercial jurisdictions<fnref n="25" />.

Although the ordinary procedure responds primarily to the logic of distributive justice and the summary procedure to that of commutative justice<fnref n="26" />, the existence of judgments that reveal some overlaps between these two forms of justice is well documented in many parts of the peninsula. Whether it a question of setting the just wage for artisans in Venice, Florence or Padua, resolving commercial disputes in Turin, compensating Roman landowners or establishing the legal threshold for interest-bearing loans in usury trials in Corleone, judges, legislators and magistrates often hold these two ideals of justice together, rather than separating or opposing them<fnref n="27" />.

<footnote n="22">²² SICILIANO VILLANUEVA, *Estimatori, stimatori*, cit.</footnote>

<footnote n="23">²³ On this point, see M. BARBOT, *Incertitude ou pluralité? Les conflits sur les droits fonciers et immobiliers dans la Lombardie d'Ancien Régime*, in A. INGOLD, J. DUBOULOZ (eds), *Faire la preuve des droits sur le sol. Droits et savoirs en Méditerranée (Antiquité-Temps modernes)*, Rome 2011, pp. 275-301.</footnote>

<footnote n="24">²⁴ On ordinary procedure, see P. SELLA, *Il procedimento civile nella legislazione statutaria italiana*, Milan 1927 (in particular pp. 216-267); M. ASCHERI, *Tribunali, giuristi e istituzioni: dal medioevo all'età moderna*, Bologna 1989; Id., *Il processo civile tra diritto comune e diritto locale: da questioni preliminari al caso della giustizia estense*, in «Quaderni storici», 101 (1999), pp. 355-387; A. MONTI, *Iudicare tamquam deus. I modi della giustizia senatoria nel Ducato di Milano tra Cinque e Settecento*, Milan 2003.</footnote>

<footnote n="25">²⁵ On summary proceedings, see A. LATTES, *Studi di diritto statutario. I. Il procedimento sommario o planario negli statuti*, Milan 1886; V. PIERGIOVANNI, *Statuti, diritto comune e processo mercantile*, in El dret comú i Catalunya, Barcelona 1998, pp. 131-151; Id., *La giustizia mercantile*, in M. G. DI RENZO VILLATA (ed), *Il diritto fra scoperta e creazione. Giudici e giuristi nella storia della giustizia civile*, Naples, Jovene, 2003, p. 409-430; CERUTTI, *Giustizia sommaria*, cit.</footnote>

<footnote n="26">²⁶ See, in this regard, ASCHERI, *Il processo civile tra diritto comune e diritto locale*, cit., and S. CERUTTI, *Nature des choses et qualité des personnes. Le Consulat de commerce de Turin au XVIIIᵉ siècle*, in «Annales. Histoire, Sciences Sociales», 6 (2002), pp. 1491-1520.</footnote>

<footnote n="27">²⁷ See, in this regard, the cases analysed by F. TRIVELLATO, *Salaire et justice dans les corporations vénitiennes au XVIIᵉ siècle: le cas des manufactures de verre*, in «Annales. Histoire, Sciences Sociales», 54-1 (1999), pp. 245-273; CERUTTI, *Giustizia sommaria*, cit.; A. DANI, *Il processo per danni dati nello Stato della Chiesa (secoli XVI-XVIII)*, Bologna 2006; A. CARACAUSI, *I giusti salari nelle manifatture della lana di Padova e Firenze (secc. XVI-XVII)*, in «Quaderni storici», 136 (2010), pp. 857-884; R. ROSOLINO, *Il giusto prezzo. Mercato e giustizia in una città di ancien régime (Corleone, secoli XVI-XVII)*, Bologna 2011; J. E. SHAW, ‘Contracts damned by God and by the World’: Litigating the Just Price in Early Modern Venice, in «Quaderni storici», 4 (2020), pp. 185-210.</footnote>
In *Il Dottor volgare* (1673) and other writings<sup>28</sup>, the famous 17<sup>th</sup>-century jurist Giovanni Battista De Luca<sup>29</sup> illustrates the functioning of justice by evoking a geometric metaphor that is also present in many allegorical and textual representations found in early modern Italy<sup>30</sup>. In its distributive version, De Luca asserts, justice is similar to a circle or a sun that projects its rays at different distances, while the other facet of justice, the commutative one, has to be imagined as a square whose sides, signifying their arithmetic equality, «are of equal length and none can exceed the others»<sup>31</sup>.

Moving from this metaphor, it can be said that the attempt of harmonisation that Italian magistrates and judges try to perform is not very far from the challenge posed by the famous geometric-mathematical problem of «squaring the circle».

Before the German scientist Ferdinand von Lindemann proved its impossibility in 1882, in the wake of subjective probabilism and relativism that pervaded many scientific fields<sup>32</sup>, many early modern mathematicians had come to the conclusion that the main goal to be achieved in solving this problem should be to obtain the closest approximation between the areas of the two figures<sup>33</sup>. As several studies have shown, in the same historical period a similar way of reasoning also exists in other fields of knowledge, from medicine to law, all of which are inclined to value approximation and the judgement of authorities as a suitable tools for approaching the «truth of facts»<sup>34</sup>.

<footnote n="28"><sup>28</sup> G. B. DE LUCA, *Il dottor volgare, ovvero Il compendio di tutta la legge civile, canonica, feudale e municipale nelle cose più ricevute in pratica, diviso in quattro volumi*, Florence, Battelli 1840 [first edition 1673], book I, pp. 119-124; ID., *Il Principe cristiano pratico, Reverenda Stamperia della Camera Apostolica*, Roma 1680.</footnote>

<footnote n="29"><sup>29</sup> On De Luca’s biography, see A. MAZZACANE, *Giambattista De Luca avvocato e curiale*, in G. B. DE LUCA, *Lo stile legale*, Bologna 2010, pp. 19-41.</footnote>

<footnote n="30"><sup>30</sup> This is the case, for instance, of the engravings on the registers of the civil court of Bologna in 18th century, as it is shown by B. FAROLFI, *Suum unicuique. Giustizia e mercato nell'antico regime*, in P. CAFARO, G. DE LUCA, A. LEONARDI, L. MOCARELLI, M. TACCOLINI (eds), *La storia economica come impegno. Saggi in onore di Angelo Moioli*, Milan 2015, pp. 64-77, p. 72. On the rich iconography of justice in medieval and early modern Italy, see M. SBRICCOLI, *La benda della Giustizia. Iconografia, diritto e leggi penali dal medioevo all'età moderna*, in ID., *Ordo Iuris. Storia e forme dell'esperienza giuridica*, Milan 2003, pp. 47-95.</footnote>

<footnote n="31"><sup>31</sup> *Ibid.*, p. 123.</footnote>

<footnote n="32"><sup>32</sup> Within a very rich literature, see I. HACKING, *The Emergence of Probability. A Philosophical Study of Early Ideas about Probability*, Cambridge 1975; L. DASTON, *Baconian Facts, Academic Civility, and the Prehistory of Objectivity*, in A. MEGILL (ed), *Rethinking Objectivity*, Durham-London 1994, pp. 37-63; J. FRANKLIN, *The Science of Conjecture: Evidence and Probability before Pascal*, Baltimore-London 2001.</footnote>

<footnote n="33"><sup>33</sup> See, in this regard, F. CARMAGNINI, *Della quadratura del circolo e del doppiamento del cubo*, Florence 1751; J.-E. MONTUCLA, *Histoire des recherches sur la quadrature du cercle*, Paris 1831 [first edition 1754]; E. W. HOBSON, *Squaring the Circle: A History of the Problem*, Cambridge 1913.</footnote>

<footnote n="34"><sup>34</sup> See R. AJELLO, *Continuità e trasformazione dei valori giuridici dal probabilismo al problematicismo*, in «Rivista storica italiana», XCVII/3 (1985), pp. 884-931; M. MECCARELLI, *Arbitrium. Un aspetto sistematico degli</footnote>
With regard to the question of the value of things, the relevance of the analogy with the squaring-the-circle problem can be found in the reasoning of the Neapolitan mathematician Elia del Re, who, within the same book (the *Aritmetica e Geometria prattica*), discusses how to «reduce a square to a circle, and a circle to a square» and addresses the question of the «fair valuation of buildings and farms»<fnref n="35" />, showing a certain ‘air de famille’ between these two topics.

Published in 1697, Elia del Re’s treatise is part of a vast body of literature whose origins date back to the first medieval cadastres<fnref n="36" />, which gives rise, in the mid-19th century, to a formal academic discipline called «estimo»<fnref n="37" />.

**3. How to make a just estimation (and what could be appraised)?**

Due to their link with direct taxation, early modern manuals of «estimo», like their medieval counterparts, are primarily concerned with the valuation of fixed and immovable properties, such as land and buildings. However, many books also devote considerable attention to movables such as furnishings, artworks, and working instruments<fnref n="38" />.

<footnote>ordinamenti giuridici in età di diritto comune, Milan 1998; R. AGO, *Una giustizia personalizzata. I tribunali civili di Roma nel XVII secolo*, in «Quaderni Storici», 2 (1999), pp. 389-412; S. CERUTTI, G. POMATA (eds), *Fatti: storie dell'evidenza empirica*, special issue of «Quaderni Storici», 108 (2001); B. J. SHAPIRO, *A Culture of Fact: England, 1550-1720*, New York 2003; A. DANI, *Un'immagine secentesca del diritto comune. La teoria delle fonti del diritto nel pensiero di Giovanni Battista De Luca*, Bologna 2008; G. ROSSI, *La forza del diritto: la communis opinio doctorum come argine all'arbitrium iudicis nel processo della prima età moderna*, in *Il diritto come forza, la forza del diritto. Le fonti in azione nel diritto europeo tra medioevo ed età contemporanea*, Turin 2012, pp. 33-61.</footnote>

<footnote n="35">³⁵ E. DEL RE, *Aritmetica e Geometria prattica*, Naples, Troyse e Pietroboni, 1697, vol. I, pp. 36 and 198. On the circulation of this manual within the Italian peninsula, see G. BRUSA, *Metodo e prassi estimativa dal XVI sec. agli anni '70 del XX sec.*, Sant'Arcangelo di Romagna 2007.</footnote>

<footnote n="36">³⁶ R. ZANGHERI, *Catasti e storia della proprietà terriera*, Turin 1980; M. BARBOT, *Gli estimi, una fonte di valore*, in ALFANI, BARBOT (eds), *Ricchezza, valore, proprietà in età preindustriale*, cit., pp. 23-27; BARBOT, CATTINI, DI TULLIO, MOCARELLI (eds.), *Stimare il valore dei beni*, cit.</footnote>

<footnote n="37">³⁷ On the origins of this discipline, still taught today in architecture and engineering faculties, see L. IACOPONI, *Teoria e pratica estimativa in Italia fra XVIII e XX secolo*, in BARBOT, CATTINI, DI TULLIO, MOCARELLI (eds), *Stimare il valore dei beni*, cit., pp. 97-122.</footnote>

<footnote n="38">³⁸ By the way, the distinction between movable and immovable goods is not purely physical, but is primarily defined by legal criteria, as it is shown by P. LANARO, *La restituzione della dote: il gioco ambiguo della stima tra beni mobili e beni immobili (Venezia tra Cinque e Settecento)*, in «Quaderni Storici», 135 (2010), pp. 753-778, and R. AGO, *Les biens meubles, une propriété qui ne crée pas d'appartenance?*, in S. BARGAOUI, S. CERUTTI, I. GRANGAUD (eds), *Appartenance locale et propriété au Nord et au Sud de la Méditerranée*, Aix-en-Provence 2015 (https://books.openedition.org/iremam/3419?lang=it).</footnote>
As often directly indicated in the titles and preambles, this literature is intended for all those who are potentially called upon to perform the function of appraiser<fnref n="39" />. In early modern Italy, this role could be performed not only by the aforementioned «periti stimatori», but also by «common friends», i.e. trusted persons freely chosen by the parties, or by judges, who must sometimes settle a dispute over prices or choose between two contradictory appraisals<fnref n="40" />. This third possibility explains the reason why among the authors of these books, in addition to numerous mathematicians, architects, surveyors, bricklayers, tax officials, craftsmen, second-hand dealers and traders, it is also possible to find several jurists and other legal professionals. This is the case, for instance, of the «doctor in law» Niccolò Festasio from Modena<fnref n="41" />, the Tuscan lawyer Antonio Maria Fineschi<fnref n="42" />, or the civil judge Giulio Cesare Giussani, member of the Council of Jurists («Collegio dei Giureconsulti») of Milan<fnref n="43" />, who in 1615 publishes an entire treatise – the *Tractatus de precio et æstimatione secundum ius civile* – dedicated to valuation and the procedural rules it requires<fnref n="44" />.

One of the most interesting elements of Giulio Cesare Giussani’s work is the distinction that is made between two distinct categories of objects: the *inestimabilia*, i. e. the things which cannot be valued, and goods to which it is legally possible to attribute an economic value<fnref n="45" />. Taking up and expanding on a legal principle dating back to Roman law, according to which

<footnote n="39">³⁹ Some manuals go even further than this wide audience, addressing anyone interested in knowing the value of their movable or immovable properties: this is the case, for example, of T. BERIA, *Instituzioni pratiche per l'Estimo de' beni stabili e mobili ed altre riguardanti il giudizio di perizia ed altre riguardanti il giudizio di perizia indirizzate a' giovani apprendisti che vogliono abbracciare tal professione: opera utile non solo alli medesimi ma ancora alli misuratori agrimensori capimastri mastri da muro ed a qualunque persona possidente case e beni*, Turin, Regia Stamperia Reale, 1796.</footnote>

<footnote n="40">⁴⁰ See the case quoted by SICILIANO VILLANUEVA, *Estimatori, stimatori*, cit., and BARBOT, CATTINI, DI TULLIO, MOCARELLI (eds), *Stimare il valore dei beni*, cit.</footnote>

<footnote n="41">⁴¹ N. FESTASIO, *Tractatus de æstimo, et collectis*, Mutina, Paulum Gadaldium et Fratres, 1569. About this treatise, see A. GABBA, *Un antico trattato di estimo nella Biblioteca Universitaria di Pavia*, in «Bollettino della Società Pavese di Storia Patria», CIV (2004), pp. 265-274.</footnote>

<footnote n="42">⁴² A. M. FINESCHI, *Regole teorico-prattiche e rustico-legali per fare le stime per uso non solo degli Stimatori, quanto ancora per istruzione dei Giudici e dei Curiali*, in Siena, da Vincenzo Pazzini, 1785.</footnote>

<footnote n="43">⁴³ For more information on this judge, see A. MONTI, *L'intervento 'pubblico' nei rapporti contrattuali privati e la stima dei beni. La prassi lombarda della datio in solutum (secoli XVI-XVII)*, in BARBOT, CATTINI, DI TULLIO, MOCARELLI (eds), *Stimare il valore dei beni*, cit., pp. 67-80.</footnote>

<footnote n="44">⁴⁴ G. C. GIUSSANI, *Tractatus de precio et æstimatione secundum ius civile*, Mediolani, Heronymum Bordonum, 1615.</footnote>

<footnote n="45">⁴⁵ It should also be noted that in Italy, unlike in other contexts (such as France), the terms «cosa» and «bene» are often used as synonyms, as it is pointed out by G. CRIVELLARI, *Beni immobili e mobili*, in *Il Digesto Italiano* cit., vol. V, 1890-1899 (1899), pp. 638-649, and A. SACCHI, *Cosa*, ibid., pp. 215-217.</footnote>
«æstimatio rei dotalis facit venditionem»<fnref n="46" />, Giussani states that all things which are estimated – precisely because they are estimated – are to be considered fully available to those who give them up, and are therefore legally transferable or alienable to other subjects.

The status of inestimable, in turn, is far from fixed once and for all<fnref n="47" />. As Giussani points out, and as it also is written in the Statutes of the Duchy of Milan<fnref n="48" />, with the exception of human bodies and coins – which, respectively, «have no price» and «do not need to be valued»<fnref n="49" /> –, «in certain cases of necessity» (e.g. a war or a famine)<fnref n="50" />, even «sacred» or «common» things can be valued and, consequently, transferred<fnref n="51" />.

Since valuation procedures play a decisive role in defining what is available and can be exchanged<fnref n="52" />, all the manuals recommend that appraisers accurately reconstruct the legal framework in which estimation takes place. Some authors go even beyond this general advice and openly suggest that the contractual arrangements in which the goods are transferred directly affect the valuation criteria to be adopted. This is the case, for example, for the treatises by Tommaso Beria and Antonio Pacini, which are respectively entitled *Istituzioni pratiche per l'Estimo de' beni stabili e mobili* and *Il notajo principiante istruito*<fnref n="53" />. While the former

<footnote n="46">⁴⁶ GIUSSANI, *Tractatus de precio et æstimatione*, p. 168.</footnote>

<footnote n="47">⁴⁷ On this regard, see M. BARBOT, 'Un bel lavor et inestimabili quasi'. *Les circuits de l'estimable et de l'inestimable dans les trésors de la cour de Milan*, in P. BOUCHERON, L. GAFFURI, J.-P. GENET (eds), *Valeurs et systèmes de valeurs (Moyen Âge et Temps modernes)*, Rome-Paris, 2016, pp. 27-37; S. CERUTTI, I. GRANGAUD (eds), *Fuori mercato. Appartenenze locali e beni nel Mediterraneo*, special issue of «Quaderni Storici», 1 (2017).</footnote>

<footnote n="48">⁴⁸ These Statutes, of which Giussani is a keen connoisseur, are promulgated in 1548 and remain in force throughout the Old Regime: A. VISCONTI, *Il diritto privato nelle Nuove Costituzioni dello Stato milanese*, in «Rivista di diritto civile» (1912-13), pp. 91-93; F. SINATTI D'AMICO, *La gerarchia delle fonti di diritto nelle città lombarde*, Florence 1962. On Giussani's comments on these customary laws, see MONTI, *L'intervento pubblico*, cit.</footnote>

<footnote n="49">⁴⁹ GIUSSANI, *Tractatus de precio et æstimatione*, cit., p. 1 and 45.</footnote>

<footnote n="50">⁵⁰ Ibid., p. 115, but see also the *Supplementi al primo, e secondo volume degli Statuti di Milano volgarizzati*, in Milano, Stamperia Galeazzi, 1773, pp. 3-4.</footnote>

<footnote n="51">⁵¹ Ibid., p. 4. Among the common» things are, first and foremost, the assets owned by the municipality: in this regard, see M. BARBOT, *Quels biens communs y-avait-il dans les Communes? Quelques remarques à partir d'un cas d'Ancien Régime*, in C. BESSY, M. MARGAIRAZ, *Les biens communs en perspective. Propriété, valeur, travail (XVIe-XXIe siècle)*, Paris 2021, pp. 45-58.</footnote>

<footnote n="52">⁵² In this perspective, see the useful observations by R. AGO, *Di cosa si può fare commercio: mercato e norme sociali nella Roma barocca*, in «Quaderni storici», 91 (1996), pp. 113-134, and CERUTTI, GRANGAUD (eds), *Fuori mercato*, cit.</footnote>

<footnote n="53">⁵³ As evidence of the strong link between valuations and law, Pacini’s work is an interesting hybrid between a treatise on estimation and a notarial manual: A. PACINI, *Il notajo principiante istruito, o sia breve trattato istruttivo sopra il civile officio del notajo diviso per maggior comodo in Tre Tomi, opera utilissima non meno al Notaio Novizio, ed a’ Giovani praticanti nella Curia Civile, quanto a chiunque brama per regolare i propri interessi, ed evitare la cagione delle Liti ne’ suoi Contratti*, in Perugia, nella Stamperia Augusta di Pier Gio. Costantini, 1774.</footnote>
emphasises the need of «*valuing an asset differently*» depending on whether it is transferred by sale, auction or inheritance<fnref n="54" />, according to the latter, the valuation carried out in the context of a transaction, i. e., a contract contract aimed at settling or avoiding a dispute, must take into account «*the price given by the parties for peace and the absence of litigation*»<fnref n="55" />. In the same vein, Giulio Cesare Giussani states that in *datio in solutum*, the basis for determining the value of the assets that the debtor must transfer to creditors is the amount of the debt that gave rise to the procedure<fnref n="56" />.

Given the importance of legally qualifying the context in which the estimation is made, all the manuals recommend also taking great care in drawing up lists and inventories. Often written in collaboration with notaries<fnref n="57" />, these supports make it possible not only identify and enumerate the assets that can be transferred and appropriated<fnref n="58" />, but also to order them according to specific criteria. This is what happens, for example, in Milan in 1654, when the second-hand dealer Carlo Ricciardi is commissioned by one of the city's largest landowners, the *Veneranda Fabbrica del Duomo*<fnref n="59" />, to value the furniture in the home of a tenant in arrears, the tailor Carlo Raffaelli, with a view to selling it at auction. After visiting the apartment, the appraiser draws up a two-column inventory, listing in the left column the items to be seized in the first instance,

<footnote n="54">⁵⁴ BERIA, *Instituzioni pratiche per l'Estimo de' beni stabili e mobili*, cit., quoted by BRUSA, *Metodo e prassi estimativa*, cit., p. 58.</footnote>

<footnote n="55">⁵⁵ PACINI, *Il notajo principiante istruito*, cit., t. III, p. 263.</footnote>

<footnote n="56">⁵⁶ GIUSSANI, *Tractatus de precio et æstimatione secundum ius civile*, cit., p. 1. This author also deals with the *datio in solutum* in a work published shortly after this treatise, entitled *Tractatus de bonis insolutum dandis, et de boni ad hastam vendendis*, Mediolani, apud Benedictum Sommascum, 1620. See, in this regard, MONTI, *L'intervento 'pubblico' nei rapporti contrattuali privati e la stima dei beni*, cit.</footnote>

<footnote n="57">⁵⁷ See, in this regard, A. OLIVIERI, *Inventario*, in *Il Digesto Italiano* cit., vol. XIII, 1901-1904 (1902), pp. 240-261, but also F. BRIEGEL, M. P. DONATO, V. THEIS (eds), *Logiques de l'inventaire. Moyen Âge-XIXe siècle*, Rennes 2024.</footnote>

<footnote n="58">⁵⁸ In this sense, these lists contribute to the construction of the quality of products traded on markets: on this topic, with reference to textile products, see W. REDDY, *The Rise of Market Culture. The Textile Trade and French Society, 1750-1900*, Cambridge-Paris 1984; C. PONI, *Standard, fiducia e conversazione civile: misurare lo spessore e la qualità del filo di seta*, in «Quaderni storici», 96 (1997), pp. 717-734, and P. MINARD, *Réputation, normes et qualité dans l'industrie textile française au XVIIIe siècle*, in A. STANZIANI (ed), *La qualità dei prodotti in Francia (XVIIIe-XXe siècles)*, Paris 2003, pp. 69-92. The latter work is inspired by the French economic school of the *Economie des Conventions*. See F. EYMARD-DUVERNAY, *Conventions de qualité et formes de coordination*, in «Revue économique», 2 (1989), pp. 329-359, and O. FAVEREAU, O. BIENCOURT, F. EYMARD-DUVERNAY, *Where do markets come from? From (quality) conventions!*, in O. FAVEREAU, E. LAZEGA (eds) *Conventions and Structures in Economic Organisation*, Cheltenham 2002, pp. 213-252.</footnote>

<footnote n="59">⁵⁹ On this institution, still existing today, see M. BARBOT, *Una Fabbrica imprenditrice? L'azione imprenditoriale degli uomini della Fabbrica del Duomo di Milano fra età moderna e contemporanea (XVII-XIX secc.)*, in F. AMATORI, A. COLLI (eds), *Imprenditorialità e sviluppo economico. Il caso italiano (secc. XIII-XIX)*, Milan 2009, pp. 377-384.</footnote>
and in the right one the items to be confiscated only if the sale of the first set of things proves insufficient to cover the debt (see Figure I).

While the first column includes carpets, paintings, linen, ready-to-wear clothing and a series of devotional objects (many of which are described as broken or deteriorated), the second column lists various raw or semi-finished fabrics, a bust, a wheelbarrow, a loom and several sacks for transporting fabrics.

<table><caption>Figure I. «Inventario di stima delle robbe di Carlo Raffaelli quali sono presso la Veneranda Fabbrica del Duomo in consegna del monitionero e delle robbe lasciate al Raffaelli da me Carlo Riccardi pattaro» (17/8/1654)</caption><tr><td>Un capotto d'ormesino L. 4, et una cappa di saglia cottonata L. 4</td><td>Un pezzo di tela sangallo verde et un pezzo di canepo L. 4</td></tr><tr><td>Un parro de calzoni, et gippone nero L. 2, et un gippone d'ormesino nero da donna L. 1</td><td>Un paro di maniche di fondo di saglia cremesi L. 2</td></tr><tr><td>Due gipponi de veluto a opera da donna L. 4</td><td>Un paro di maniche di color d'oliva L. 3</td></tr><tr><td>Una robba da donna guarnita di raso L. 4</td><td>Un busto da huomo verde L. 4</td></tr><tr><td>Un parro di maniche di rassa rossa secha, et altri aldini della sudetta robba L. 1</td><td>Un fatto di varie pezze et robbe disfatte L. 8.10</td></tr><tr><td>Due tapetti con franza sono di occhiorata di filo, con bombaso L. 3</td><td>Mantini et pezzette n. 15 tutti diversi L. 7</td></tr><tr><td>Due bustini di canepo, et altro non finito, et varii pezzi di busti pure di canepo L. 2</td><td>Serviette anchora da finire n. 8 L. 5</td></tr><tr><td>Sugamani diversi n. 6, L. 1.10</td><td>Una fodretta picina de strazzi bianchi L. 8</td></tr><tr><td>Sottocalzoni di tela para trè, L. 3.10</td><td>Una cassa di noce antica L. 13</td></tr><tr><td>Undeci tovaglie diverse L. 15</td><td>Un telaro L. 10</td></tr><tr><td>Una testa di S. Pietro martire con cornice intagliata et profili d'oro L. 24</td><td>Una cariola L. 4</td></tr><tr><td>Una testa di S. Gioseffo con cornice come sopra L. 24</td><td>Cinque sacchi di canepo buoni con maniche L. 6</td></tr><tr><td>Un San Carlo incorniciato rotto, un altro San Carlo incorniciato alla romana, un altro S. Carlo senza cornice L. 24</td><td></td></tr></table>
Due teste, una di nostro Signore, una della
madonna ambedue incorniciate di nero L. 18
Due quadri vecchi longhi dalli 2 sino alli 3 brazza
L. 6

Source: Archive of the *Veneranda Fabbrica del Duomo di Milano, Capo XXIV (Case in Milano), Cartella 238, Porta Orientale* (amounts expressed in Milanese *lire*)

As the bold amounts in Figure I clearly show, the dividing line between these two columns is not merely economic (the most expensive items on one side, the cheapest on the other), but it reflects the aspiration to establish a hierarchy between what is essential for survival and what is not, leaving the tailor Carlo Raffaelli with the items necessary to continue his work as a tailor. But how is the value of these different items determined?

A first point to underscore in this regard is the fact that the valuation manuals openly acknowledge the approximate nature of the valuation. Whereas Giulio Cesare Giussani does not hesitate to qualify the experts' judgement as an opinion («æstimatio est opinio»<fnref n="60" />), according to Antonio Pacini, these judgements always contain a certain degree of roughness («all'incirca»<fnref n="61" />). However, this circumstance does not affect the accuracy and correctness of the final result, provided that this result is obtained in accordance with the procedural requirements imposed by laws and with the inspection techniques described in the manuals. These techniques, in turn, correspond to four different typologies<fnref n="62" />. The first one, known as «a misura», consists of calculating weights, lengths, widths, heights and surfaces using local units of measurement and metric conventions. The second, called «a vista», «a corpo» or «a impressione», requires breaking down the objects to be estimated «piece by piece» – physically or abstractly<fnref n="63" /> – and examining them using the five senses, which, as already seen, justifies the absence of physical malformations required of estimators. The third technique, often referred to as «storica» (historical), is based on the chronological ordering of a series of written or oral information and data obtained from notarial deeds, previous valuations, testimonies, receipts, registers or accounting documents.

<footnote n="60">⁶⁰ GIUSSANI, *Tractatus de precio et æstimatione*, cit., p. 9.</footnote>

<footnote n="61">⁶¹ PACINI, *Il notajo principiante istruito*, cit., vol. II, p. 165.</footnote>

<footnote n="62">⁶² These techniques are still used today, as pointed out by IACOPONI, *Teoria e pratica estimativa*, cit.</footnote>

<footnote n="63">⁶³ The exercise of abstraction required of estimators is highlighted, for instance, by G. MORRI, *L'economo istruito nelle fabbriche*, in Faenza, Archi, 1787.</footnote>
The fourth technique, often referred to as «indirect» as opposed to the first three, which are called «direct», requires a purely theoretical and conjectural approach, and consists of comparing the prices of similar goods traded in the same space-time context. Although accepted by many manuals, this last technique arouses a certain amount of mistrust, if not outright derision<fnref n="64" />: some authors recommend it only if the first three are impracticable, while others accept its use only in the case of very standardised objects, for which the expertise and practical and empirical knowledge of appraisers are not strictly necessary.

The «direct» techniques, for their part, are not considered strictly alternative, but can be used in combination. To take the example of two Neapolitan manuals published in the 16th and 17th centuries, the first suggests adopting them in a discretionary order, while the second recommends starting with visual inquiry, correcting this technique with measurement, and using historical evidence for final verification<fnref n="65" />.

Despite these differences, all authors agree that direct investigations, if carried out correctly, make it possible to quantify the «intrinsic» or «absolute» value of things, and to isolate it from the «extrinsic» value (also called «accidental» or «relative»). The main criterion for distinguishing between these two entities is mathematical: while intrinsic value always has a positive sign, extrinsic value, on the contrary, can add or subtract value. But let's take a closer look at these two valuation conventions and to their calculation methods.

**4. The two sides of value and their quantification**

Remaining unchanged throughout the early modern age, the notion of intrinsic value adopted by estimation books fully corresponds to the definition formulated by the first treatises on political economy, according to which this quantity coincides with the production costs of

<footnote n="64">⁶⁴ This is the case, for example, of the book by C. TRINCI, *Trattato delle stime de' beni stabili, per istruzione, e uso degli stimatori, opera di Cosimo Trinci pistojese, Agrimensore, stimator pubblico e corrispondente dell'Accademia de' Georgofili*, in Firenze, nella Stamperia di Gaetano Albizzini, 1755, pp. 15-16.</footnote>

<footnote n="65">⁶⁵ See, respectively, G. LAPAZZAIA, *Libro d'Arithmetica, e Geometria, e delle Misure, de' Territori, e Fabriche a costume del Regno di Napoli, ed anche d'Apprezzi*, in Napoli, Stamperia di Niccolò Migliaccio, 1727 [first edition 1592], and T. TELESE, *Prattica delli Apprezzi feudali, o Burgensatici, cosi di Stati, e Terre, come di Territori, Fabriche, di annue entrate fiscali, dote, antefato, e sopra arredamenti, e gabelle*, in Napoli, Savio, 1643 (both quoted by BRUSA, *Metodo e prassi estimativa*, cit. pp. 4-5 and 13-16).</footnote>
goods. These costs, in turn, result from the sum of the value of raw materials and of the labour required to transform them<fnref n="66" />.

Another important point of convergence is that intrinsic value is considered the most suitable convention for fixing the «immanent», «true», «real» or «minimum» economic value: by using these expressions, the authors of estimation books suggest that things always have a basic material substrate of value on which – to quote judge Giussani n – «everyone agrees» («omnes consentiunt»)<fnref n="67" />.

However, despite its aura of objectivity, intrinsic value is not based solely on physical and «real» elements. The virtues of this conventions, in fact, seem to lie also, and above all, in the opportunity it offers for matching the material attributes of things to the social characteristics of individuals who made them, who use them or for whom they are intended<fnref n="68" />.

In the wake of Vitruvius and Sebastiano Serlio’s theories on how to construct buildings based on the socio-economic status of their occupants<fnref n="69" />, several authors argue, for example, that the economic value of a dwelling certainly depends from the quality of its materials and the effort required to work them, but that these factors also have the power to express the social position of their actual or potential inhabitants. In this way, referring to intrinsic value makes it possible to distinguish at first glance an aristocratic palace, constructed in stone – the «noble» material par excellence – from more modest dwellings, built mainly of wood and brick<fnref n="70" />.

Similar remarks are made with regard of all objects described as rare and precious, whose production techniques, often highly complex and elaborate, are considered a direct sign of the dignity and prestige of their creators and users<fnref n="71" />. Appraisal reports, for their part, take full

<footnote n="66">⁶⁶ On the definition of value in the treatises of pre-classical economists, see G. MAIFREDA, *L'economia e la scienza. Il rinnovamento della cultura economica tra Cinque e Seicento*, Rome 2010 and J.-Y. GRENIER, *Avant la grande transformation. Valeur et prix dans la pensée préclassique*, in M. VALLERANI (ed), *Valore delle cose e valore delle persone*, cit., pp. 329-368.</footnote>

<footnote n="67">⁶⁷ GIUSSANI, *Tractatus de precio et æstimatione*, cit., p. 149.</footnote>

<footnote n="68">⁶⁸ These three dimensions are often perceived as intertwined: see VALLERANI (ed), *Valore delle cose e valore delle persone. Dall'Antichità all'Età moderna*, cit.</footnote>

<footnote n="69">⁶⁹ M. VITRUVIO POLLIONE, *De i proprii luoghi degli edificij privati et communi, et delle maniere convenienti a ogni qualità di persone*, in ID., I dieci libri di architettura tradotti e commentati da Daniele Barbaro, in Venetia, appresso Alessandro de' Vecchi, 1629, book XVI, chapter VIII. In the 16th century, Serlio took up and completed this theory in ID., *Architecturæ liber septimus*, Frankfurt am Main, A. Wechel & J. Strada, 1575.</footnote>

<footnote n="70">⁷⁰ In this regard, see M. BARBOT, *La casa da nobile et sa valeur: le cas de Milan (XVIᵉ-XIXᵉ siècle)*, in «Revue Belge de Philologie et d'Histoire», 94 (2016), pp. 393-406.</footnote>

<footnote n="71">⁷¹ Thus, with regard to the valuation of noble palaces and their furnishings, T. BERIA, *Instituzioni pratiche per l'Estimo de' beni stabili e mobili*, cit.</footnote>
account of this kind of considerations: for example, in the long series of appraisals carried out
on the current Milan’s city hall, *Palazzo Marino*, the social identity of its occupants is
systematically included among the intrinsic components of value<sup>72</sup>, and the same applies to the
furnishings of the rooms of *Palazzo Crivelli*, another famous aristocratic residence in the city<sup>73</sup>.

If intrinsic value is not completely neutral to subjective or social criteria, its «objective» and
material nature is evoked for essentially rhetorical and performative purposes, with the aim of
marking a clear contrast with extrinsic value, which, on the contrary, includes any type of factor
that influences the value of things without having any close physical connection with them. In
order for the final result of the estimation to be as legitimate and justifiable as possible<sup>74</sup>, the
main challenge is therefore to calculate these two conventions in a different manner.

Similar to the definition provided by the manuals, the methods proposed for quantifying
the main component of intrinsic value, i.e. production costs, remain unchanged throughout the
early modern period. All authors agree that, once «direct» investigations have given a
sufficiently broad and solid empirical basis, it is necessary to classify the quantities and kinds
(wood, marble, stone, gold, silver, etc.) of materials used, to fix their unit costs according to
their state of preservation («old», «new», «broken», «very broken»<sup>75</sup>, etc.), and finally add the
cost of labour, taken from written documents (contracts, reports, accounting records) or from
oral information provided by craftsmen, suppliers or witnesses. There is also broad consensus
that both the cost of raw materials and the methods of remuneration for working time (daily,
hourly, by piecework, etc.<sup>76</sup>) significantly change from one jurisdiction to another. This

<footnote n="72">⁷² In 1578, for example, the palace is appraised by engineer Giovanni Battista Cairati, who, in order to justify the intrinsic value of the residence, refers to «*the quality of the person [...]*» who occupies it: M. FORNI, *The Negotiations for the Palazzo that belonged to the deceased Tomaso Marino. Palazzo Marino and its Real Estate Evaluations and Use from the Sixteenth to the Eighteenth Centuries*, in M. BARBOT, L. LORENZETTI, L. MOCARELLI (eds), *Property Rights and their Violations. Expropriation, Seizure and Confiscation in Europe and its Settlements, 16th-20th centuries*, Berne 2012, pp. 37-64.</footnote>

<footnote n="73">⁷³ M. BARBOT, *La casa da nobile et sa valeur*, cit.</footnote>

<footnote n="74">⁷⁴ On the use of value as a mean to justify prices, see the interesting remarks of the sociologist L. BOLTANSKI, *Pragmatique de la valeur et structures de la marchandise*, in «Annales. Histoire, Sciences Sociales», 3 (2017), pp. 607-629.</footnote>

<footnote n="75">⁷⁵ On this work of qualification, see M. BARBOT, *A ogni casa il suo prezzo. Le stime degli immobili della Fabbrica del Duomo di Milano fra Cinque e Settecento*, in «Mélanges de l’École Française de Rome. Italie et Méditerranée», 119/2 (2007), pp. 249-260. The classification of assets is also useful for identifying and qualifying second-hand goods, as shown by G. TODESCHINI, *Seconda mano*, cit.</footnote>

<footnote n="76">⁷⁶ On the different measures of working time, see C. MAITTE, D. TERRIER (eds.), *Les temps du travail. Normes, pratiques, évolutions (XIVᵉ-XIXᵉ siècle)*, Rennes 2014.</footnote>
circumstance, in turn, makes it impossible to «*to establish a general rule of valuation*»<sup>77</sup> and reinforces the importance of employing local estimators, whose status as citizens is a direct proof of their territorial belonging and their knowledge of the «*local customs*» («*stili del paese*»)<sup>78</sup>.

In addition to production costs, another technique for calculating intrinsic value, valid only for leased properties, is the income capitalisation method, which consists of multiplying the rent lease by a fixed percentage (generally 3-5%). Although it has been theorised since the 16<sup>th</sup> century<sup>79</sup>, this method is considered relatively marginal for two reasons: the limited use of lease agreements compared to other forms of property occupation<sup>80</sup>, and the shared refusal to calculate purely conjectural rents, set exclusively on the basis of market trends. Classified as as «extrinsic» elements of value, these virtual or potential rents are the subject of much criticism by authors because their determination, relying on purely abstract criteria, seems to disregard the practical knowledge and empirical skills required of appraisers<sup>81</sup>.

In addition to virtual rents, extrinsic value consists of a series of factors which, at least until the end of the 17th century, varies considerably from one author to another. In his 1595 book *Il Perito arithmetico, e geometrico*, Jacob Stainer from Udine, for instance, describes as extrinsic «*the effect of physical contiguity between two buildings*»<sup>82</sup>, arguing that, if a person wanted to acquire ownership of both properties, the benefit that he or she would obtain would be such that the intrinsic value should be increased «*by ten per cent*»<sup>83</sup>. For his part, Tebaldo Telese (1643) observes that in the Kingdom of Naples, the presence of a legal burden – «*such as easements, mortgages or litigation*» – resultes in a depreciation of 10-20% compared to the intrinsic value<sup>84</sup>. This kind of rule is also attested outside the Neapolitan context. Suffice it to mention

<footnote n="77"><sup>77</sup> Thus E. DEL RE, *Aritmetica e Geometria prattica*, cit., part II, book V, p. 198.</footnote>

<footnote n="78"><sup>78</sup> On this point, see BARBOT, CHAUVARD, MOCARELLI (eds), *Questioni di stima*, cit., and M. BARBOT, *The Justness of Æstimatio and the Justice of Transactions: Defining Real Estate Values in Early Modern Milan*, in DE MUNCK, LYNA (eds), *Concepts of Value in European Material Culture*, cit., pp. 133-150.</footnote>

<footnote n="79"><sup>79</sup> BRUSA, *Metodo e prassi estimativa dal XVI sec.*, cit.</footnote>

<footnote n="80"><sup>80</sup> On the limited spread of short-term leases in early modern Italy, see FARON, HUBERT (eds), *Le sol et l'immeuble*, cit.</footnote>

<footnote n="81"><sup>81</sup> This is, for example, the position of TRINCI, *Trattato delle stime de' beni stabili*, cit., p. 16.</footnote>

<footnote n="82"><sup>82</sup> J. STAINER, *Il Perito arithmetico, e geometrico*, Udine, Schiratti, 1672 [first edition 1595] (quoted by BRUSA, *Metodo e prassi estimativa*, cit., p. 10).</footnote>

<footnote n="83"><sup>83</sup> Ibid.</footnote>

<footnote n="84"><sup>84</sup> T. TELESE, *Prattica delli Apprezzi*, cit. (quoted by G. BRUSA, *Metodo e prassi estimativa*, cit., p. 15). Various applications of this rule are illustrated by F. STRAZZULLO, *Edilizia e urbanistica a Napoli dal '500 al '700*, Naples 1968 (p. 31).</footnote>
an appraisal carried out in 1601 on a house in the centre of Milan: based on its physical and material components, the house is estimated at 4,700 imperial *lire*, but the appraiser decides to deduct 700 *lire* (that is 17.5% of the initial value) «due to the serious expenses and infinite damage caused by the dispute with the neighbouring nuns of Santa Clara»<fnref n="85" />.

If some valuation rules appear to have a supra-local application, from the end of the 17th century onwards, appraisers' manuals also show a clear tendency to embrace a broader and more consensual definition of extrinsic value. In order to illustrate this convention, many authors refer to fluctuations caused by inflation, economic downturns or, more generally, the dynamics of the supply and demand of goods and services<fnref n="86" />. These references, in turn, mark the beginning of a growing acceptance and application of the «indirect» method based on the calculation of virtual rents: since these amounts are set by comparing the prices most often applied for similar goods, they are considered as good indicators of market trends. However, the increasing legitimisation of this valuation method and the related convention of extrinsic value does not lead to a loss of importance of intrinsic value: at the end of the *Ancien Régime*, for example, the lawyer Antonio Maria Fineschi (1785) states that intrinsic value is and must be considered as the «*only true and fundamental basis of value*»<fnref n="87" />. This position is also shared by many other authors, who emphasise that this convention should be preferred whenever it is necessary to choose between two contradictory appraisals or to resolve a legal dispute, suggesting that intrinsic value remains the fairest and most legally correct valuation criterion<fnref n="88" />.

**5. Conclusions: intrinsic value and squaring the circle**

Although the use of extrinsic value becomes increasingly important and influential in the 18th century, the unaltered preference accorded to the intrinsic value raises questions about the reasons for its long persistence. In this regard, the historian Bert de Munck posits a first

<footnote n="85">⁸⁵ Archive of the *Veneranda Fabbrica del Duomo di Milano, Capo XXIV, Cartella 247, foglio 92*. On this example, see BARBOT, *A ogni casa il suo prezzo*, cit.</footnote>

<footnote n="86">⁸⁶ For example, see A. CAPRA, *Geometria famigliare et instruttione pratica*, Cremona, Zanni, 1671. Similar considerations are also put forward by the jurist DE LUCA, *Il dottor volgare*, cit., book IV, part III, p. 51.</footnote>

<footnote n="87">⁸⁷ FINESCHI, *Regole teorico-prattiche e rustico-legali per fare le stime*, cit., p. 5.</footnote>

<footnote n="88">⁸⁸ This applies in particular in cases of breach of contract known as «lesione enorme», or «ultra dimidium» (more than half the just price). Even at the beginning of the 19th century, the intrinsic value is the legal basis for determining whether or not there is a breach: see, in this regard, M. MASTROFINI, *Della maniera di misurare la lesione enorme ne' contratti*, in Milano, Giovanni Silvestri, 1833.</footnote>
hypothesis. He attributes the spread of this valuation convention to cultural and epistemological
factors linked to the magical and religious status attributed to raw materials and to the creative
and ‘demiurgic’ action of craftsmen, *homines faber* capable of shaping and enhancing these
materials. Conversely, Bert De Munck argues that the disappearance of intrinsic value, which
he documents in 18th-century Netherlands, can be explained by the effects of the scientific
revolution and the changing role of artisans following the first signs of the industrial
revolution<fnref n="89" />.

Examining the procedural dimensions of valuation processes, and analysing them in light
of the ideals of justice in which they are embedded, one might propose another interpretation,
already indirectly evoked by Giovanni Levi in an article published in the early 2000s<fnref n="90" />. Seeking
to explain the overlappings of commutative and distributive principles of justice which are
revealed by many archival sources, Giovanni Levi outlines the consistency of this phenomenon
with the functioning of early modern societies. Completely saturated with classifications and
hierarchies, these societies experience dynamics of emulation and competition that arise almost
exclusively within homogeneous socio-economic groups<fnref n="91" />. This circumstance means that
demands for justice coming from the social world, as well as the responses provided by political
and judicial authorities, do not aspire to absolute and universal equality, nor to the delimitation
of autonomous ‘spheres of justice’ rigidly separated from one another<fnref n="92" />, but rather to the
recognition of the uniqueness and specificity of individuals’ condition in a context of a relative
equality, defined in reference to the social segment to which they belong. It is also interesting
to note that similar logics are at work in another economic and political field particularly
sensitive to equity issues such as direct taxation, to which the estimation literature, as we have
seen, are closely linked. In many jurisdictions of early modern Italy<fnref n="93" />, the predominant system
of taxation consists of applying two principles that are today strictly separated: one personal,

<footnote n="89">⁸⁹ DE MUNCK, *Guilds, product quality and intrinsic value*, cit.</footnote>

<footnote n="90">⁹⁰ G. LEVI, *Æquitas versus Fairness. Reciprocità ed equità fra età moderna e contemporanea*, in «Rivista di storia economica», 3 (2003), pp. 195-204.</footnote>

<footnote n="91">⁹¹ VALLERANI (ed), *Valore delle cose e valore delle persone*, cit.; J.-Y. GRENIER, *Modèles de la demande sous l'Ancien Régime*, in «Annales. Économie, Société, Civilisations», 42-3 (1987), p. 497-527.</footnote>

<footnote n="92">⁹² We refer, in this regard, to the theory of Michael Walzer in his famous book *Spheres of Justice. A Defense of Pluralism and Equality*, Oxford 1985.</footnote>

<footnote n="93">⁹³ For a more comprehensive overview of the fiscal systems of the Italian states, see L. PEZZOLO, E. STUMPO, *L'imposizione diretta in Italia dal Medioevo alla fine dell'Ancien Régime*, in S. CAVACIOCCHI (ed), *La fiscalità nell'economia europea, secc. XIII-XVIII*, Florence 2008, pp. 75-98; L. PEZZOLO, *Tassare e pagare le tasse tra Medioevo e prima età moderna*, in *Historiae. Scritti per Gherardo Ortalli*, Venice 2013, pp. 237-251.</footnote>
which recognises differences in treatment based on the socio-professional status of taxpayers,
and the other real, which aims to mitigate the effects of these differences by taking into account
the physical and material characteristics of the assets and wealth they own<fnref n="94" />.

As Giovanni Levi points out (without referring specifically to taxation<fnref n="95" />), recognising the uniqueness of each individual’s situation on the basis of a contractual and arithmetic idea of equality, defined in relation to each social group, is a very complex and difficult task to achieve, as it requires the best possible compromise between a set of statutory and subjective variables and a set of impersonal and objective ones<fnref n="96" />. Since the criteria for classifying individuals into groups are themselves variable and manifold, the equilibrium between these two sets of variables can only be reached case-by-case. It is precisely this subtle process of adjustment «in situation» that is entrusted to estimation.

As both an objective and subjective valuation convention, capable of taking into account
the «quality of persons» and the «nature of things», intrinsic value is ultimately particularly
well suited to articulate the commutative «square» and the distributive «sphere» of justice,
while the procedural dimension of estimation, for its part, ensures that the judgement of
estimators can both be legal and socially legitimate.

<footnote n="94">⁹⁴ The acceptance of this dual logic of taxation by taxpayers can be observed in their claims and requests for exemptions, as I have shown in M. BARBOT, *Proprietà, giurisdizione e cittadinanza in una misura di fiscalità diretta. Tassare gli immobili nella Milano d'Età moderna*, in «Quaderni Storici», 49 (2014), pp. 809-834; EAD., *De l'Æquitas à la Fairness. Taxation, droit et justice au prisme de deux mesures de fiscalité directe* (Italie, XVIᵉ-XVIIIᵉ et XXIᵉ siècles), in V. ALBE, J. COMMAILLE, F. LE BOT (dir.), *L'échelle des régulations politiques, XVIIIᵉ-XXIᵉ siècles*, Lille 2019, pp. 47-58.</footnote>

<footnote n="95">⁹⁵ Levi's reflections essentially focus on consumers' behaviour, also analysed in G. LEVI, *Comportements, ressources, procès: avant la révolution de la consommation*, in J. REVEL (ed), *Jeux d'échelles. La micro-analyse à l'expérience*, Paris 1996, pp. 187-207, p. 195.</footnote>

<footnote n="96">⁹⁶ Similar considerations can be found in VALLERANI (ed), *Valore delle cose e valore delle persone*, cit.</footnote>