With the desire to rid logic of the epistemological taint the "experimental logic" of the pragmatic movement has the strongest sympathy. But the proposal to effect this by the excision of the act of knowing appears to experimental logic to be a case of heroic but fatal surgery. Prima facie a logic with no act of knowing presents an uncanny appearance. What sort of logical operations are possible in such a logic and of what kind of truth and falsity are they capable?
Before taking up these questions in detail it is worth while to note the character of the entities that "merely are" with which analytic logic proposes exclusively to deal. In their general form they are "terms" and "propositions," "sense-data" and universals. We are struck at once by the fact that these entities bear the names of logical operations. They are, to be sure, disguised as entities and have been baptised in a highly dilute solution of objectivity called "subsistence." But this does not conceal their origin, nor does it obscure the fact that if it is possible for any entities that "merely are" to have logical character those made from hypostatized processes of logical operations should be the most promising. They might be expected to retain some vestiges of logical character even after they have been torn from the process of inquiry and converted into "entities that merely are." Also it is not surprising that having stripped the act of knowing of its constituent operations analytic logic should feel that it can well dispense with the empty shell called "mind" and, as Professor Dewey says, "wish it on psychology." But if the analytic logician be also a philosopher and perchance a lover of his fellow-man, it is hard to see how he can have a good conscience over this disposition of the case.
Turning now to the character of inference and of truth and falsity which are possible in a logic which excludes the operation of knowing and deals only with "entities that are," all the expounders seem to agree that in such a logic inference must be purely deductive. All alleged induction is either disguised deduction or a lucky guess. This raises apprehension at the start concerning the value of analytic logic for other sciences. But let us observe what deduction in analytic logic is.
We begin at once with a distinction which involves the whole issue.[23] We are asked to carefully distinguish "logical" deduction from "psychological" deduction. The latter is the vulgar meaning of the term, and is "the thinker's name for his own act of conforming his thought" to the objective and independent processes that constitute the real logical process. This act of conforming the mind is a purely "psychological" affair. It has no logical function whatever. In what the "conforming" consists is not clear. It seems to be merely the act of turning the "psychological" eye on the objective logical process. "One beholds it (the logical process) as one beholds a star, a river, a character in a play.... The novelist and the dramatist, like the mathematician and logician, are onlookers at the logical spectacle."[24] On the other hand, the term "conforming" suggests a task, with the possibilities of success and failure. Have we, then, two wholly independent possibilities of error—one merely "psychological," the other "logical"? The same point may be made even more obviously with reference to the term "beholding." The term is used as if beholding were a perfectly simple act, having no problems and no possibilities of mistakes—as if there could be no mis-beholding.[25]
But fixing our psychological eye on the "logical spectacle," what does it behold? A universal generating an infinite series of identical instances of itself—i.e., instances which differ only in "logical position." If in a world of entities that "merely are" the term "generation" causes perplexity, the tension is soon relieved; for this turns out to be a merely subsistential non-temporal generation which, like Hegel's generation of the categories, in no way compromises a world of entities that "merely are."
Steering clear of the thicket of metaphysical problems that we here encounter, let us keep to the logical trail. First it is clear that logical operations are of the same reproductive repetitive type that we have found in the associational logic of empiricism, and in the logic of the objective universal. Indeed, after objective idealism has conceded that the finite mind merely "witnesses" or at most contributes only in an "infinitesimal" degree to the logical activity of the objective universal, what remains of the supposed gulf between absolute idealism and analytic realism?
It follows, of course, that there can be no place in analytic logic for "procedure by hypotheses." However, it is to the credit of some analytic logicians that they see this and frankly accept the situation instead of attempting to retain hypotheses by making them "accidents" or mere "auxiliaries" of inference. On the other hand, others find that the chief glory of analytic logic is precisely that it "gives thought wings"[26] for the free construction of hypotheses. In his lectures on "Scientific Methods in Philosophy" Mr. Russell calls some of the most elemental and sacred entities of analytic logic "convenient fictions." This retention of hypotheses at the cost of cogency is of course in order to avoid a break with science. Those who see that there is no place in analytic logic for hypotheses are equally anxious to preserve their connections with science. Hence they boldly challenge the "superstition" that science has anything to do with hypotheses. Newton's "Hypotheses non fingo" should be the motto of every conscientious scientist who dares "trust his own perceptions and disregard the ukase of idealism." "The theory of mental construction is the child of idealism, now put out to service for the support of its parents." "Theory is no longer regarded in science as an hypothesis added to the observed facts," but a law which is "found in the facts."[27] The identity of this with Mill's doctrine of hypotheses as "found in things" is obvious.
As against the conception of hypotheses as "free," "winged," constructions of a psychical, beholding, gossiping mind we may well take our stand with those who would exclude such hypotheses from science. And this doubtless was the sort of mind and sort of hypotheses Newton meant when he said "Hypotheses non fingo."[28] But had Newton's mind really been of the character which he, as a physicist, had learned from philosophers to suppose it to be, and had he really waited to find his hypotheses ready-made in the facts, there never would have been any dispute about who discovered the calculus, and we should never have been interested in what Newton said about hypotheses or anything else. What Newton did is a much better source of information on the part hypotheses play in scientific method than what he said about them. The former speaks for itself; the latter is the pious repetition of a metaphysical creed made necessary by the very separation of mind from things expressed in the statement quoted.
Logically there is little to choose between hypotheses found ready-made in the facts and those which are the "winged" constructions of a purely psychical mind. Both are equally useless in logic and in science. One makes logic and science "trifling," the other makes them "miraculous." But if hypotheses be conceived not as the output of a cloistered psychical entity but as the joint product of all the beings and operations involved in the specific situation in which logical inquiry originates, and more particularly in all those involved in the operations of the inquiry itself (including all the experimental material and apparatus which the inquiry may require), we shall have sufficient continuity between hypotheses and things to do away with miracle, and sufficient reconstruction to avoid inference that is trifling.
It is, however, the second contribution of analytic logic that is the basis of the enthusiasm over its prospective value for other sciences. This is the discovery that terms and propositions, sense-data, and universals, are not only elements of logical operation but are the simple, neutral elements at large which science is supposed to have been seeking. "As the botanist analyzes the structures of the vegetable organism and finds chemical compounds of which they are built so the ordinary chemist analyzes these compounds into their elements, but does not analyze these. The physical chemist analyzes these elemental atoms, as now appears, into minuter components which he in turn must leave to the mathematicians and logicians further to analyze."[29]