A survey of these proof: show, that in every one some fact is cate!*orically asserted. No one can venture to say, for instanee, that the same object :.rives rise to different impressions. unless his own experience has furnished him with this knowledge. Once question or deny the reason assigned. and the skeptical conclusion can no longer be maintained by the skeptic without. dog matic assertion of the reason as self-evident or without the production of a new reason, which, when disputed, shares the fate of its predecessor. In other words. upon examination it is clear that skepticism cannot recommend itself as an escape from the danger of dogmatic assertion or of an infinite regress of proofs; for we cannot accept skepticism without proof. and if the skeptic is right, proof involves either unwarranted dog matism or impossible regress of argument to infinity.
But it may be said that this inconsistency and illogicality of skepticism is no refutation of skep ticism. Perhaps not ; but it makes it necessary for the skeptic to bring forward other reasons for the unfaith that is in him; and when he does, these new reasons can be met in the same way. The skeptic must assume the validity of his argu ment in order by argument to convict his oppo nent of error or of unreasonableness. lint, again. it may be asked: Why may not the skeptic hold to his skepticism without attempting to establish his position or to dislodge his opponent? The answer is that to cherish any view without proof is to be dogmatic, and this is what the skeptic is, above all things, anxious to avoid. But still, again, it may be urged that instead of believing in the impossibility of knowledge, one may mere ly doubt• its possibility. It is often said by writers against skepticism that a skeptical skep ticism is unassailable. In one sense it is. If a man will persist in listening to no reason and in observing no laws of thought, then no argu ment directed against him will reach him, so long as he takes refuge behind the bulwark of unthink ingness. But what we can do is to convince our solres by valid reasoning that skepticism. wheth er dogmatic or doubting, is untenable by a rea sonable being. That is, if we follow the laws of thought we cannot become skeptical with re gard to all our knowledge. however skeptical we may be on smne of its details. To summarize our argument so far, let us say that we cannot reasonably doubt an•lbing without good reason, and good reason is known reason, and known rea son implies the validity of knowledge.
The insight into this truth enables its to ap preciate the skeptic's rationality perhaps better than he does himself. Whenever we find a skep tic in philosophy we find a man who is trying to reason consistently, and who in this endeavor to be consistent even goes so far as to say that all knowledge is impossible. In such a case it is better worth our while to see what his funda mental assumptions are than to grieve or be merry over his conclusions. Now, one assumption
is made by every skeptic, as by every other thinker—viz. that a thinker must make the ob jects of his thought consistent. It is the demand for consistency which drives all thinkers on to their conclusions, whatever these may be. Let, us now examine this logical demand for consistency, and see what it is and what it involves.
This logical demand for consistency involves, as a presupposition, that there be some object-matter in dealing with which a thinker is to be consistent. In other words, consistency is a relation, thought thus to obtain between objects. To think eon sistently is to think objects into consistency. The law of consistency, like all other laws of thought (see Louie), is a law directing the disposition which thought is to make of its objects. It is true that we may demand consistency in our pro cesses of thought as well as in the disposition of objects. lint this is because we objectify our thinking processes. We may then compare one process with another, or one part of a process with another part, and may find that they are not consistent. We may then come to demand order in our, thinking as well as order in the things we think about. But it must be under stood that this is possible only when our own thinking is a 11 l i ll g we think about; i.e. only when thought becomes an object of thought. We may therefore safely say that eonsisteney as a logical law is a demand that the objects of thought he made to accord with en ell other. It is this demand which impels the child to constitute his sensations into an ordered world of experi ence. Ile tries to think them into sonic consistent relation with each other. Such au attempt to a large extent succeeds, but the success is slow. The work is done by means of categories (q.v.), or prineiples of connection which the thinker rec ognizes as obtaining between different objects. One may say that the reduction of experience into consistency is nothing but the ascertainment of such relations, or principles of connection, be tween objeets as make it possible to think them together without having them conflict with each other as they appear in thought. For instance, in a certain di;;11 on a stove 1 see one minute a dear, transparent, solid cube; the next minute in the same pan I see a clear, transparent liquid. In order to be able to think these two objects as one, which the contimtity of the objects under my gaze prompts me to do, I must be able to think of the cold, solid cube as changing into the liquid. Change is thus a category, or a pri» ciple of connection recognized as existing between two objects and making them consistent with each other. In the ease of our example there are other categories; e.g. those of attribute and substance; and. provided I think of the experience as my experience, those of subject and object.