These considerations clearly demonstrate that we have general ideas, which are not merely concrete ideas used as examples, and if we can employ them in the manner just indicated, where a light superficial recollection is all that is necessary, we can equally well use them in their more legitimate character, as signs of certain general utilities.
XV—ERRORS WITH RESPECT TO GENERALISATION
Generalisation has been the bane of European philosophy. It has monopolised well-nigh the whole metaphysical attention. It has been considered the radical fact of mind from which all others have grown, whereas it is no more than a method for abbreviating recollection. It neither reveals to us new things, nor reduces the multiplicity of things actually existing.
Plato insisted on the importance of general thought as against the fluctional idealism of Heraclitus, but he was wholly mistaken as to the nature of general ideas. He thought they were external objects—also types and causes of primary objects. But patterns are not causes, and general ideas are quite obviously suggested by things, not things derived from general ideas. The notion that the general idea is either the cause, or an image and revelation of the cause, of things is an error of perennial recurrence. In some form or other it is always with us.
Plato also taught that general ideas are recollections of knowledge acquired in the condition prior to embodiment, which the objective experience of this life serves to revive. These several doctrines are somewhat inconsistent with each other. The last is interesting but lacks confirmation.
Aristotle admitted the superiority of general over particular ideas, and thought that the former corresponded to some specially important part of objects called the 'essence.'
This is nearer the truth. The essence of an object is that part of it, which being present, a given sentimental result follows, or may be expected to follow, or may be made to follow. A certain experience of things is necessary before we can know what is the objective minimum consistent with some sentimental utility. If things are classified with due regard to their utilities, the essence will be the same as the general idea. It is however not true that the essence or any other part of the object causes the sentimental effect (VII).
A common form of the generalistic superstition is to suppose that a thing is explained or sufficiently accounted for by classifying it.
In all philosophies of Greek derivation—the Asiatic seem to be free from this defect—reason is considered to be 'the bringing of a thing under a class-notion,' and when this is done we are supposed to know the thing completely. An elaborate and utterly false dialectic has been erected on this foundation.
No doubt our first attempt at explaining a thing is to refer it to a general idea—to classify it. This usually suggests something to add to the bare phenomenon by way of explanation or hypothesis. But only if we have a prior knowledge of the general idea, derived from things better known than the present phenomenon. The general idea is simply a short formula of that prior knowledge. Suppose we thoroughly know a body of similar things a, b, c, and also reduce them to the general image X; then on seeing d and noticing that it is like a, b, c, we briefly think, 'Oh, it is X,' which excuses us from studying it further. We at once transfer to d our whole knowledge of a, b, c, and in this ideal transfer the explanation consists—not in the classification. The transfer is often tacit—if explicit it is an 'argument.'