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.'
If there has been no better known _a_, _b_, _c_, it is evident that
the mere generalisation of new facts _d_, _e_, _f_, will not add
anything to our knowledge of _them_. In deduction we should only
return to them the knowledge just extracted from them. We should be
explaining things by themselves--reasoning in a circle[12].
The _unity_, which explains is not the general idea. It is a unity of
function or service, and may include things utterly heterogeneous, and
therefore incapable of being reduced to a common idea. The pen in my
hand consists of wood and metal; if I generalise them into Matter--the
nearest class that includes both--I do not thereby explain the pen.
But it is explained by the unity of service: the wood and metal
contribute to form one instrument for writing.
The best results of modern science are discoveries of utilities
(inventions); discoveries of the relations of sequence among objects,
which enable us to predict their arrival years in advance; of
coexistences on the great cosmic scale (geographical and stellar
exploration); of co-inherence of properties in individual objects
(chemistry). Yet science is still too generalistic. It runs too much
to classification and nomenclature, which is nothing but _memoria
technica_. Modern biology presents a curious return of Platonism. The
general idea is not indeed put forward as the cause of individuals,
but a particular concrete animal is found who closely resembles the
general idea, and it is imagined that an animal like him was the
original cause of all animals of his species. When it happens--as
it occasionally must in a thorough-going system of phenomenal
classification--that the average or general idea falls between two
species, no individual can be found to represent it with the desired
exactness. In this case it is supposed by evolutionists that the
intermediate animal has existed but is now extinct. These are the
'missing links' so badly wanted to complete the evolutionary scheme.
[Footnote 10: 'Mysticism is neither more nor less than
ascribing objective existence to the subjective creations
of our own faculties, to ideas or feelings of the
mind.'--_Logic_, chapter on 'Fallacies.']
[Footnote 11: With equal plausibility it might be argued that
we have no particular ideas, because it is difficult if not
impossible to observe and remember all the details of any
object. Our most particular ideas are slightly abstract,
and in the process of forgetting they become more and more
abstract, until they disappear altogether.]
[Footnote 12: Mill's nominalistic tendencies led him to the
same conclusion: 'Our general ideas contain nothing but what
has been put into them, either by our passive experience, or
by our active habits of thought; and the metaphysicians in all
ages, who have attempted to construct the laws of the universe
by reasoning from our supposed necessities of thought, have
always proceeded, and only could proceed, by laboriously
finding in their own minds what they themselves had formerly
put there, and evolving from their ideas of things what they
had first involved in those ideas.'--_Logic_, Bk. V. c. 3. §
3.]