# The Historical Library of Diodorus the Sicilian/Preface

Translation by G. Booth (1814)
ALL mankind are under a great obligation of gratitude to those that have written universal histories; forasmuch as there has been an honourable contest amongst them by their labours and pains, to be helpful to others in the due conduct and management of the common affairs and concerns of this present life. For whereas they usher in a sort of wholesome instruction, without any hazard to the person; so they thereby also procure to their readers art and skill in politics above the ordinary rate, with great ease and security. For knowledge gained by experience, though it brings a man to an aptness to be quick in discerning what is most advisable in every particular case, yet such knowledge is attended with many toils and hazards. And thus he that was the most experienced man among the heroes, viewed many cities, and came well to understand and pry into the minds and tempers of men, yet it was with many troubles and misfortunes: but knowledge of what was well or ill done by others, gained by history, carries along with it instructions, freed from those misfortunes that others have before experienced.
Besides, these historians have used their utmost diligence to reduce all men, in their consideration of them, (who are united and related one to another in the same common nature and original, though far distant each from the other as to place and time), under one and the same head, and common order, as if they were servants herein to the Divine Providence. For as Providence having marshalled the stars (visible to us) in a most beautiful frame and order, and likewise conjoined the natures of men in a common analogy and likeness one to another, incessantly wheels about every age, as in a circle, imparting to each what is before by fate shared out and allotted for them; so these historians, by committing to writing the common actions of men through the whole world, as if they were affairs only of one city, represent their labours as one entire account, and common repertory and treasury of human transactions. For it is a desirable thing to be in a capacity to make use of the mistakes of others, the better to order the course of our own lives, and in the various events and accidents that may befal us, not to be then at a loss, and seeking what is to be done, but rther to be able to imitate what has been well done. And certainly, as to counsel and advice, all prefer ancient men before those that are young, because of their prudence gained by a long experience. But history goes as far beyond the knowledge of old men, as we are sure it does surmount all their experience in multitude of examples. So that any man may justly look upon it as a thing most profitable and advantageous, to make use of this upon all occasions and accidents of this life. As for young men, it teaches them the wisdom and prudence of the old, and increases and improves the wisdom of the aged: it fits private men for high places; and stirs up princes (for the sake of honour and glory) to those exploits that may immortalize their names. It encourages likewise soldiers to fight the more courageously for their country, upon the hopes of applause and commendation after their deaths: and as a curb to the impious and prophane, it restrains them in some measure, upon the account of being noted to posterity, with a perpetual brand of infamy and disgrace.
What shall I say? In hopes of having the memory of their good acts recorded to posterity by historians, some have built cities, others have applied themselves to the promulgation of good and wholesome laws: many also, upon this account, have set their wits to work to invent arts and sciences for the good of mankind. And whereas complete happiness is made up of all perfections centering in one, history consequently is to bear away the prize, which is the cause of all those commendable and glorious effects; for it is most certain, she is the preserver of the virtues of worthy men in posterity; and eternal witness to the cowardice and impiety of others; and a benefactor to all mankind in general. For if a fine spun story, consisting merely of fictions told of things done among the spirits below, tends much to the promoting of piety and justice, how much more then may we conclude that history, the most noble assertrix of truth, and very metropolis (as it were) of all philosophy, may adorn the manners of men which principles of justice and honesty? For there is not a man (through the infirmity of human nature) that lives scarce a moment of an entire eternity, but is extinguished and gone for ever after this life; and with those who never did any thing commendable in their life-time, all their enjoyments and comforts perish with them. But those who have signalized themselves by virtuous actions, are made famous in every age, their praises being proclaimed, as it were, by a divine voice from history.
I judge it therefore honourable and commandable, and a piece of admirable wisdom and prudence, to purchase that glory which is immortal, with labours and sufferings that are but short and temporal. It is confessed by all, concerning Hercules, that while he was here upon earth, he voluntarily undertook great and continual labours, and ran through many dangers, that, by doing good to mankind, he might gain the reward of immortal fame. And as to other men, some are honoured as heroes, others deified as gods, and all by the help and advantage of history, which has transmitted their virtues to posterity, and caused the remembrance of them to be immortal. Other monuments endure but for a little time, and are often ruined and destroyed by various accidents; but the force and vigour of history pierces through the whole world, and time itself, (which consumes all other things), is its keeper, handing it down to posterity for ever.
History likewise conduces much to make a man eloquent, than which nothing in more commendable; for by this Grecians excel barbarians, and the learned those who are ignorant: and by this art alone it is, that one single person many times prevails over multitudes.
To conclude__Whatever is done, appears to be such either as to quantity or quality, as the eloquent rhetorician is pleased to make it. And such we call good men, men of high esteem for excellent language, as those that by qualification have attained the highest pitch of virtue. But this art of speaking well, is divided into several parts: that part which is poetical, seems to delight more than to profit the auditor; that which relates to the making of laws tends more to coercion than instruction; and the other parts either contribute nothing at all to our well-being; or they are as hurtful one way, as they are useful and profitable another; and some of them even oppose the truth with downright lies.
But history only (wherein words and things agree) comprehends in writing, what is both pleasant and profitable; for who cannot discern but that it persuades to justice; condemns the wicked and vicious; praises the good, and greatly improves the understanding of the readers? And therefore, when we saw these sort of writers deservedly in great esteem, we were stirred up to an earnest study of prosecuting the same subject.
But when we seriously consider the authors that have been before us, though we highly approve of their method and design, as far as we may justly; yet we conceive their writings are not altogether composed to the due measure of profit and advantage as they ought to be. For whereas to profit the reader, it is necessarily requisite, that many and various circumstances of affairs be related; many set forth the wars of only one nation, or one single city; for very few have begun their histories from ancient times, or have made it their business to write of the affairs of all nations in general, to these our days. And those that do, some of them fix no certain time to the several transactions they write of; and others altogether pass over the affairs of the barbarians. And some there are that never mention the ancient mythologies, but slip them by, because of the difficulty of the subject. Some that have begun to write, have been prevented by death, and so have left their works imperfect. And none who have hitherto set themselves to this business, have brought down their history below the times of the Macedonians: for some have broke off at Philip, others at the acts of Alexander, and others at his successors or posterity. And though many great and considerable actions since those times, to these our days, have been upon the stage, yet no historian has hitherto undertaken to set them forth in one entire tract, by reason of the tediousness of the work. And in regard that in those writings which we have, the times and actions that have been comprehended in them, are huddled together in several volumes, written by various and several authors, it is a very difficult matter either to understand, or remember them.
Having therefore diligenty perused and examined the tracts of the several authors, I determined to compose an entire history, from which the reader might reap much advantage, with little labour and pains: for he who endeavours, to the utmost of his power, to comprehend in his writings the memorable affairs and actions of the whole world, (as of one single city), bringing down his history from the most ancient times to his own age, though he set upon a work certainly most laborious, yet he will perform that which, when finished, will be undoubtedly most useful and profitable. For hence, every man may, as out of a common fountain, draw what is convenient and serviceable for his own private use. For as to them that have a desire to employ themselves in tumbling and turning over so many authors, first, such cannot easily get so many books together as are necessary for their use; and then again, by reason of the differing relations and multitude of authors, they can scarcely understand the matters related.
But one general history, in one entire tract, as it may be quickly and readily perused, so the understanding of the subject matter, with far more ease, goes along with the reading. Yes, this sort of history excels all others, as far as the whole is more useful than the part; as the entire thing is more desirable than that which is divided; and that which fixes the exact periods of tme, more than that which leaves the time uncertain and unknown, when things related were done.
Perceiving, therefore, that such a work would be of mighty use and advantage, but that it would require both a long time, and a great deal of labour and pains, we spent thirty years time in the composing of it; and for that purpose travelled through a great part of Asia and Europe, with many hazards and difficulties, that we ourselves might be eye witness of most of the parts and places that were necessary for the carrying on of our design in this work. For, through the ignorance of places, not only common writers, but even those who are reputed the most eminent, have committed many errors and mistakes. The chief cause, and that which most helped forward the design, (which, though thought impossible, is now fully completed and perfected), was the strong and constant desire we had of composing such a work. Many helps likewise were afforded to us at Rome, for the carrying on of what we had undertaken in this kind. For that noble city, whose power is stretched out as far as to the utmost corners of the earth, (being that we had been there a long time an inhabitant), furnished us with many things ready at hand for our purpose. For being born in Agyrus in Sicily, and having in a great measure learnt the Roman language, by means of the frequent commerce of Romans in that island, I diligently collected out of their ancient records, what I found concerning the memorable actions of this empire.
We have begun our history with the mythologies handed down to us, as well those of the Grecians as of the barbarians, seriously weighing and considering, as far as we were able, what every one of them have related of things done in ancient times. Having now finished what was designed, though not yet exposed to public view, before that be done, we shall declare something briefly concerning the whole work.
Our first six books comprehend the affairs and mythologies of the ages before the Trojan war, of which the first contain the barbarian, and the next following almost all the Grecian antiquities. In the eleven next after these, we have given an account of what has been done in every place from the time of the Trojan war, till the death of Alexander. In the three-and-twenty books following, we have set forth all other things and affairs, till the beginning of the war the Romans made upon the Gauls; at which time Julius Caesar the emperor, (who upon the account of his great achievements was surnamed Divus) having subdued the warlike nations of the Gauls, enlarged the Roman empire, as far as to the British isles; whose first acts fall in with the first year of the hundred and eightieth olympiad, when Herodes was chief magistrate at Athens. But as to the limitations of times contained in this work, we have not bound those things that happened before the Trojan war, within any certain limits, because we could not find any foundation whereon to rely with any certainty.
According to Apollodorus, we have accounted fourscore years from the Trojan war, to the return of Heraclides: from thence to the first olympiad, three hundred and twenty-eight years, computing the times from the Lacedaemonian kings: from the first olympiad to the beginning of the Gallic war, (where our history ends), are seven hundred and thirty years: so that our whole work, (comprehended in forty books), is an history which takes in the affairs of eleven hundred and thirty-eight years, besides those times that preceded the Trojan war.
We have been the more careful to premise these things, that the reader might have the clearer prospect into the nature of the whole tract; and that those who commonly take upon them to polish and amend books, may at least be prevailed with not to corrupt other men's works. Whatever, therefore, through the whole history, is written well, let no man envy: what slips there are, (through ignorance), those who have more knowledge are very welcome to amend.
And now, having finished what we thought fit to premise, we shall endeavour to actually perform what we before promised, as to the writing of the history.

## Footnotes

* ↑ Ulysses.
* ↑ A divine person, or a God.