MS 425 (1902) - Minute Logic - Chapter I

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in the interest of psychology itself to restrain it from flowing over into the region of logic. As for abstraction I shall endeavor in the course of this volume to pit before the reader reasons for thinking that it is a wholly unpsychological matter the doctrine of which has gone far astray in consequence of the admixture pf psychology with it. Something like psychological association certainly appears in logic but in order that the relation of logical association to psycholgical association a relation mote interesting to the psychologist than to the logician may become clearly understoof it is desirable that the two theories should be developed sepearately and side by side. The notion that a normative science is necessarily of the nature of a practical art in having no independent value as a pure theory is one which

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no doubt arises naturally enough from a superficial survey. But in another chapter we shall have occasion to inquire somewhat closely into the nature of the different sciences and we shall then find that so far is it from being true that the normative character must necessarily be exclusively due to the branch of knowledge that possesses it being a mere concrete application to a practical need of a theory which in its pure development never considered that need that on the contrary this character may equally have it's origin in the circumstance that the science which presents ot os sp very abstract sp allow to from any experiential lineage that ideals alone in pace of positive facts of experience can be its proper objects. It is J.S Mill who insists that how we ought to think can be ascertained in no other way than by reflection upon those psychological laws which tach us how we must needs think. But here we have to distinguish the case

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in which the compulsion attacks to that subconscious thought over which we have no control and the case in which it attaches to conscious reasoning. In the former case there is no room for logical criticism at all. But because there is nothing to be said against our thinking in a certain way in subconcious thought when we cannot do otherwise it does not at all follow that we ought to think in that way when we have our choice between several ways of thinking. If however Mill refers to a complusion attaching to conscious thought what he no doubt has in mind is that a person ought to think the way in which he would be compelled to think if he duly reflected and made his thought clear and brought has whole knowledge to bear. But when he asserts that in such a case there is no other reason to be given for thinking in a given way than barely that the

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thinker is under complusion so to think is he not applying that Criterion of Inconceivability against which we have heard him fulminate in his finest style? It is true that Mill does not say that is no other reason in support of the conclusion but only that there is no other reason why the reasoner ought to accept the conclusion. But this makes no pertinent difference the arguments against The Criterion apply equally in this case. As before we areto distingiush to between an absolute definitive complusion of thought and a limited complusion. To say that that the reason would if he reflected sufficiently be under an absolute definitive complusion to hold a certain opinion is as was shown in the discussion of the criterion neither more nor less than to assert that the opinion is true. Now to say that a reasoner ought to believe something for no other reason than that it is true is to say that there is no reason at all why he ought to

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do so. Besides it is nonsense to sat that the science of psychology establishes such a proposition unless the subject of the belief happend to be the operatuons of the mind. Nor can it be maintained that there is a distinct logic for reasonings whose conclusions are psychological. The evident truth is that psychology never does prove a complusion of thought od an absolute definitive kind for conscious operations of the mind. It establishes only associational compulsion and with conquests over these Mr. Mill tells us the history of science terms.

Let us however come a little closer to the concrete I do not remember any treatise on logic which tells the reader that if Sortes is a man and all men are mortal then Sortes ought to be thought mortal. Mill's logic certainly says no such thing. What they all say is that Sortes must be mortal. Logical treatises never say