# An Enquiry Concerning the Principles of Natural Knowledge/Chapter 16

CHAPTER XVI
CAUSAL COMPONENTS
60. Apparent and Causal Characters. 60.1 Are there any material objects in nature? That there are such bodies is certainly an assumption habitually made in the applications of mathematics. But the assumption does not supersede the necessity for enquiry.
We may roughly summarise the properties of material objects, as here defined, by saying that they should be continuous both in time and in space. But this is just what ordinary perceptual objects appear to be. Now perceptual objects are what they appear to be; for a perceptual object is nothing else than the permanent property of its situations, that they all shall exhibit those appearances. Accordingly if a perceptual object appears to be a material object, it is a material object.
Now here a difficulty arises; for we all know that, according to Dalton’s atomic theory of chemistry, any apparently continuous substance is a discrete collection of molecules, and that furthermore, according to the more recent theories, a molecule is a discrete collection of electric charges. Accordingly, as we are told, if we could take the minutest drop of water and magnify it, the phenomena would be analogous to those of a swarm of flies in a room.
It would appear therefore that we are mistaken in classifying a drop of water as being a material object.
60.2 The position that we seem to have arrived at is that on the one hand a drop of water is a material object, because it appears to be one and it is whatever ​it appears to be, and that on the other hand it is really something quite different.
Such paradoxes mean that vital Getiactions have been overlooked. We must distinguish between the drop of water as it appears, the event which is its situation, and the character of the event which causes the event to present that appearance. Namely, there is the appearance of the drop of water. ‘This is character No. 1 of the event, the apparent character, and is a material object. Again there is the character of the event which is the cause of character No. 1. This is character No. 2 of the event and is its causal character. According to the doctrine of science, character No. 2 is not a material object.
60.3 But why trouble about causal characters? What has pushed science into their consideration? The impelling reason is the complex bewildering relationships of the apparent characters. Apparent characters essentially involve reference to percipient events, and may be very trivial qualities of the events which they characterise. For example, all delusive perceptual objects are apparent characters of events.
In the case of a delusive perceptual object character No. 2 of its situation has no existence, except so far as the event is necessarily still a ‘passive condition’ according to the nomenclature of Chapter VII of Part II. The active conditioning events for a delusive perceptual object must be sought elsewhere than in its situation. Let us confine ourselves to the consideration of non-delusive perceptual objects, that is, to physical objects.
60.4 But the line of separation between delusive and non-delusive perceptual objects is not quite so clear ​as we might wish. The definition of delusiveness and non-delusiveness is sufficiently obvious, namely, a perceptual object is non-delusive when it is the apparent character of an event which is itself an active condition for the appearance of that character as perceptible from all percipient events. In the nomenclature of Chapter VII of Part II the situation of a physical object is its ‘generating event.’
Now if this definition is to be taken to the foot of the letter, all perceptual objects are delusive; for all perception is belated. The sun which we see is the apparent character of an event simultaneous with our percipient event, and this event is about eight seconds subsequent to the generating event corresponding to that appearance of the sun. In the case of other astronomical phenomena the discrepancy is more glaring. In the case of terrestrial perceptual objects the discrepancy is less glaring in many cases, though for sounds it is very insistent and is the reason of their very indeterminate situations. But, speaking generally and admitting exceptions, for the greater part of ordinary domestic perceptions the belatedness of the apparently characterised event behind the causally characterised event is a small fraction of the percipient’s specious present.
Accordingly our knowledge of causal characters is a theory built up by ignoring this element of delusiveness in all perceptual objects, and then by introducing it as an additional correction in the exceptional cases.
61. Transition from Appearance to Cause. 61.1 But how can we pass from appearance to cause, seeing that our knowledge of nature is confined to awareness of appearance? For example, all measurement is a measurement of appearance. ​
Evidently therefore causal characters can only be directly known to us as functions of apparent characters. They are characters of characters. For example, a quantity which we assign to a physical object as the result of some measurement is a character of its apparent character.
61.2 It is necessary however to avoid a misunderstanding; the causal character of an event is not merely a function of the apparent character of that event. It is in truth a function of the apparent characters of all events, though in general the apparent character of that event — or of an associated event of somewhat later date — is the dominant element in the formation of the function. For example, a quantity determined by measurement is a relation of the apparent character of the event to the apparent characters of other events. But it is the dominance of the apparent character which in practice makes the discovery of the causal character generally possible; for it assigns the situation of the causal character. This dominance is merely a practical aid to the discovery of causal characters and has in it no element of necessity. Indeed as causal characters are progressively discovered, scientific theory assigns causal characters to events which are destitute of, apparent character — namely the events forming the ether in empty space and time.
61.3 So far the explanation of causal characters has exhibited them as the outcome and issue from apparent characters, whereas the causal idea, which is that of science, requires the causal characters should be the origin of the apparent characters. We have to seek the reason for this inversion of ideas.
Causal characters are much simpler than apparent ​characters; are more permanent than apparent characters; and depend almost entirely on the event itself, involving other events only (in general) as passive conditions providing the necessary background of a whole continuum of nature. The climb from the sense-object to the perceptual object, and from the perceptual object to the scientific object, and from the complex scientific object (such as the molecule) to the (temporally, in a stage of science) ultimate scientific object (such as the electron) is a steady pursuit of simplicity, permanence, and self-sufficiency, combined with the essential attribute of adequacy for the purpose of defining the apparent characters.
61.4 The relations of sense-objects to their situations are complex in the extreme, requiring reference to percipient events and transmitting events. Apart from some discovery of laws of nature regulating the associations of sense-objects, it is impossible by unintelligent unsorted perception to form any concept of the character of an event from the sense-objects which might be situated there for percipients suffering from any normal or abnormal perceptions.
The first stage is the discovery of perceptual objects. These objects are first known by the instinctive ‘conveyance’ of abnormal perceptions of sense-objects associated with normally perceived sense-objects. The test of alternative possibilities of normal perception and the discovery of a permanent character in the association which can be expressed independently of any particular percipient event decides between delusive perceptual objects and physical objects.
61.5 The introduction of physical objects enables us in considering the characters of events to sweep ​aside the boundless eccentricities of abnormal perceptions. We are still at the stage of apparent characters, but rules have been attained, either by instinctive practice or by the exercise of intelligence or by the interplay between the two, by which we know what to attend to and what to discard in judging the character of an event from the situations of sense-objects. A physical object is the apparent character of its situation. Physical objects are found to be ‘material’ objects.
61.6 Science now intervenes with the express purpose of exhibiting our perceptions as our awareness of the characters of events and of relations between characters of events. All perceptions are included in the scope of this aim of science, namely, including abnormally perceived sense-objects and delusive perceptual objects.
61.7 The origin of the concept of causation (in this application of the term) is now manifest. It is that of the part explaining the whole — or, avoiding this untechnical use of ‘part’ and ‘whole,’ it is that of some explaining all. For the physical objects were obtained by discarding abnormalities, and physical objects express the characters of events, and all our perceptions (including abnormalities) arise from awareness of these characters.
61.8 But physical objects fail to satisfy the requirements of science. They lack definiteness and permanence, and are not adequate for the purposes of explanation. Now the characters of their mutual relations disclose further permanences recognisable in events and among these are the scientific objects. The gradual recognition of these permanences was at first the slow product of civilised thought without conscious direction. As regards their conscious discovery various ​stages may be discerned in scientific history, which sum up the previous growth of ideas and initiate new epochs. One stage is marked by Archimedes’ discovery of specific gravity, and another by Newton’s discovery of mass. The simplicity of what, in its relation to appearance, is so abstract was then beginning to be discovered, and also its permanence and self-sufficiency as a quality of events. A third stage is the introduction of the concept of molecules and atoms by Dalton’s atomic theory. Finally there arose the concepts respecting the ether, which we here construe as meaning the concept of events in space empty of appearances.
61.9 These causal characters, which are the characters of apparent characters, are found to be expressible as certain scientific objects, molecules and electrons, and as certain characters of events which do not necessarily themselves exhibit any apparent characters. If we follow the route of the derivation of knowledge from the intellectual analysis of sensible experience, molecules and electrons are the last stage in a series of abstractions. But a fact in nature has nothing to do with the logical derivation of concepts. The concepts represent our abstract intellectual apprehension of certain permanent characters of events, just as our perception of sense-objects is our awareness of qualities of nature resulting from the shifting relations of these characters. Thus scientific objects are the concrete causal characters, though we arrive ‘at them by a route of apprehension which is a process of abstraction. In the same way, what, in the form of a sense-object, is concrete for our awareness, is abstract in its character of a complex of relations between scientific objects. Thus what is concrete as causal is abstract in its deriva​tion from the apparent, and what is concrete as apparent is abstract in its derivation from the causal.
The ultimate scientific objects (at present, electrons and positive electric charges) are ‘uniform’ objects; and, in the limited sense of charges in the ‘occupied’ events, they are also ‘material’ objects. There does not appear to be any reason, other than the very natural desire for simplicity, for the assumption that ultimate scientific objects are uniform. Some of the atomic and ‘quantum’ properties of nature may find their explanation in the assumption of non-uniform ultimate scientific objects which would introduce the necessary discontinuities.
61.91 The causal character of the situation of a physical object is the fact that this situation contains a certain assemblage of ultimate scientific objects; namely, the fact that among the parts of this situation are various parts which are the occupied events of these scientific objects. The ‘causal components’ of a physical object are the scientific objects which occupy parts of the situation of the physical object, and whose total assemblage is what constitutes the qualities which are the apparent character which is the physical object apparent in the situation.
61.92 An adjustment, ordinarily negligible but often important, has to be made to allow for the belatedness of perception. Two situations are thus involved (even although in ordinary cases they are practically identical), namely the situation of the physical object from an assigned percipient event, and the situation of the assemblage of causal components which is the situation of the ‘real’ object.