Logical consistency

“ The problem that confronts you, then, in either kind of analysis, however formal or informal it may be, is, How shall I go to work? The first necessity is the choosing of a basis for division of the subject, whether it be in classification or partition. The necessity for this arises from the demand of the human mind for logical consistency. Life seems often wildly inconsistent, but we demand that explanation of it or any phase of it be arranged according to what seems to us some logical law of progression, some consistent point of view. ”

“ All truth whatever is one in character by possessing the inseparable attribute of complete consistency. The truthfulness of scientific knowledge is proved by its agreement with universal experience and with the fundamental logical axioms:—a thing either is or is not:—a thing cannot both be and not be:—a thing must either be or not be:—things equal to the same are equal to each other ”

“ There is total failure to unite the differences by any consistent principle, and the one discoverable system is the systematic avoidance of consistency. The single fact is viewed alternately from either side, but the sides are not combined into an intelligible whole. ”

“ While traditional logic has much to say about truth, the truth it talks about is mere formal consistency, since it declines to consider the material application of its premises. Relevance—a fundamental conception of concrete thought—is excluded because it goes with selection, with selection of the part that is useful, while formal logic professes an all-inclusive ideal. ”

“ Truth may be conveniently defined as universal consistency; or that which perfectly conforms to facts, and agrees with the widest experience, when tested by means of all our intellectual powers, the reasoning faculty in particular. The usual modern criterion of it, is consistency with the fundamental axioms of logic, and with all the great principles of nature as established by means of scientific research, such as the universality of causation, the continuity of phenomena, the indestructibility of matter and energy, the convertibility and equivalency of forces, &c. ”

“ When we infer some fact from some other fact which does not really prove it, we either have admitted, or, if we maintained consistency, ought to admit, some groundless general proposition respecting the conjunction of the two phenomena. ”

“ Thus the sceptic is forced, not merely to lay claim to absolute and certain knowledge, but to use the test of consistency itself for the purpose of disproving or questioning its own validity. Our criterion of Reality, then, has been proved infallible by the surest of methods; we have shown that its truth has to be assumed in the very process of calling it in question. ”

“ Not only however is it indispensable that the larger Logic, which embraces all the general conditions of the ascertainment of truth, should be studied in addition to the smaller Logic, which only concerns itself with the conditions of consistency ”

“ Nor is this particular conflict in our ordinary ideas yet before us in all its fatefulness, for—as if to defy the principle of consistency to the very last degree of its forbearance—we are often, if not usually, given not only to unifying our world of things in terms of just one more thing, or of persons in terms of just one more person, but also to thinking of this one more thing, or person as sui generis, as altogether different in nature and substance. ”

“ The Logic of Consistency is a necessary auxiliary to the logic of truth, not only because what is inconsistent with itself or with other truths can not be true, but also because truth can only be successfully pursued by drawing inferences from experience, which, if warrantable at all, admit of being generalized, and, to test their warrantableness, require to be exhibited in a generalized form; after which the correctness of their application to particular cases is a question which specially concerns the Logic of Consistency. ”

“ in principle and in practice, in a right track and in a wrong one, the rarest of all human qualities is consistency. ”

“ My soul sickens at the word 'consistency.' Some of my colleagues seem to regard consistency as the essence of wisdom, but I cannot understand it that way. To me, consistency implies a clinging to old ideas and customs, and is therefore a symbol of negativeness instead of progression. I want to advance:—to grow in wisdom and [Pg 7] knowledge, though that advancement means the abandonment of every past idea, however choice and excellent that idea may have seemed, either at the time of its acceptance or now. ”

“ But do not inconsistencies and negations and incongruities exist? They certainly do; everything has its opposite; and if we will take the pains to observe the processes of thought, we shall find that thought is fundamentally inconsistent. Why do we usually regard thought as a self-consistent process? Because our methods of formal logic are such. In formal logic we reason smoothly and consistently from the premises to the conclusion. If we look more deeply into thought, we shall find that such consistency is made possible by ignoring the inconsistencies necessary to the very being of thought. ”

“ There is, therefore, nothing paradoxical, but the reverse, in our being led by observation to a recognition of such truths, as general propositions, co-extensive at least with all human experience. That they pervade all the objects of experience, must insure their continual suggestion by experience; that they are true, must insure that consistency of suggestion, that iteration of uncontradicted assertion, which commands implicit assent, and removes all occasion of exception; that they are simple, and admit of no misunderstanding, must secure their admission by every mind. ”

“ For the purposes of the present Treatise, I am content that the justification of the larger extension which I give to the domain of the science, should rest on the sequel of the Treatise itself. Some remarks on the relation which the Logic of Consistency bears to the Logic of Truth, and on the place which that particular part occupies in the whole to which it belongs, will be found in the present volume (Book II., chap. iii., § 9) . ”

“ Consistency is agreement; and when thou sayest, I have done wrong, it is inconsistent with wrong to do right. Consistency is to do wrong, because wrong has been done. Wouldst thou recommend consistency with wrong? ”

“ Bradley that we are justified “in the intelligent refusal to accept as final an theoretical criterion which actually so far exists,” and that the “action of narrow consistency must be definitely given up.” ”

“ Definition, though belonging still more to the other and larger kind of logic than to this, is a necessary preliminary to this. The end aimed at by Formal Logic, and attained by the observance of its precepts, is not truth, but consistency. It has been seen that this is the only direct purpose of the rules of the syllogism; the intention and effect of which is simply to keep our inferences or conclusions in complete consistency with our general formulæ or directions for drawing them. ”

“ Next to consistency, the great principle of causation constitutes the most essential part of all natural truth, and to deny the operation of this principle in particular cases of mental action, simply because we, with our very finite powers, cannot in the extremely imperfect state of our knowledge, yet fully explain some of the most difficult, complex, transient, and ever-changing phenomena of will and consciousness, is contrary to the most weighty evidence. ”

“ On the other hand, there is a true duty of consistency, which regards the spirit rather than the letter, and prompts us not to grasp foolishly at the ideal, like a child crying for the moon, but to push steadily towards the ideal by a faithful adherence to the right line of reform, and by ever keeping in view the just proportion and relative value of all moral actions. ”

“ And if several of the more difficult sciences are still in so defective a state; if not only so little is proved, but disputation has not terminated even about the little which seemed to be so; the reason perhaps is, that men's logical notions have not yet acquired the degree of extension, or of accuracy, requisite for the estimation of the evidence proper to those particular departments of knowledge. ”

“ The laws, then, of the formation of character being the principal object of scientific inquiry into human nature, it remains to determine the method of investigation best fitted for ascertaining them. And the logical principles according to which this question is to be decided, must be those which preside over every other attempt to investigate the laws of very complex phenomena. For it is evident that both the character of any human being, and the aggregate of the circumstances by which that character has been formed, are facts of a high order of complexity. ”

“ What we have termed the absolutistic logic ends, as far as method in social matters is concerned, in a substitution of discussion of concepts and their logical relations to one another for inquiry. Whatever form it assumes, it results in strengthening the reign of dogma. ”

“ The unchangeable laws of logic, too, are instances of the eternal truth. The principles of the validity of thought are entirely independent of individuals, of the passage of time, and of the environment of man. "Our thought cannot advance in the definite work of building up science without producing and employing a definite logical structure, with fixed principles ”

“ No matter what show of logic may drive us into the corner, our instinctive moral sense prohibits us from entertaining the theorem that the single self who conducts the argument, albeit he is its cause, its designer, its engineer, and its authority, is the sole and absolute Reality, — the only being in existence having such compass, such sovereign judgment, such self-determining causality. ”

“ Our question in the present discussion being this, “What determines us to acknowledge as real one rather than another system of particular facts?” we have here pointed out that the first determining principle, namely, the Ought, requires us to acknowledge at each moment as real certain particular facts which, even while they are conceived as limiting, constraining, and so determining our acts, are also conceived as thereby enabling us even now to accomplish our will better than we could if we did not acknowledge these facts. ”

“ Another logical movement springs from those whom a correlation of fact within the unity of a system altogether failed to satisfy. There must also be development of the correlated terms from a single principle. Form and content must not only correspond one to the other. ”

“ If you adopt, as absolute, a criterion of right which is so only relatively, your results will not be absolutely right. Those who trust to their senses become, as it were, slaves to objective existences. Those alone who are guided by their intuitions find the true standard. ”

“ If, respecting the origin and nature of things, we make some assumption, we find that through an inexorable logic it inevitably commits us to alternative impossibilities of thought; and this holds true of every assumption that can be imagined. If, contrariwise, we make no assumption, but set out from the sensible properties of surrounding objects, and, ascertaining their special laws of dependence, go on to merge these in laws more and more general, until we bring them all under some most general laws ”

“ Those who have dispensed with the assumption of such a universal standard, have only been enabled to do so by supposing that a moral sense, or instinct, inherent in our constitution, informs us, both what principles of conduct we are bound to observe, and also in what order these should be subordinated to one another. ”

“ The example we took before of an A proposition in the conjunctive form—
'If kings are ambitious, their subjects always suffer'
may be converted into
'If subjects suffer, it may be that their kings are ambitious,'
i.e. among the possible causes of suffering on the part of subjects is to be found the ambition of their rulers, even if every actual case should be referred to some other cause. It is in this sense only that the inference is a necessary one. But then this is the only sense which formal logic is competent to recognise. To judge of conformity to fact is no part of its province. ”

“ In the first two modes they are also resolved into laws more certain, in other words, more universally true than themselves; they are, in fact, proved not to be themselves laws of nature, the character of which is to be universally true, but results of laws of nature, which may be only true conditionally, and for the most part. ”

“ Thus our involuntary adhesion to the first, and our inability to hold the last, answer to their respective claims as measured by the fundamental test of credibility. The instinct justifies the logic: the logic accounts for the instinct. It was hinted at the outset, that an inquiry into our knowledge by means of our knowledge must, if rightly conducted, be consistent in its results—that the analysis of Philosophy must agree with the synthesis of Common Sense. ”

“ The mistake is of the more elementary character when the attempt to establish the laws of thought, or a general criterion, is made by help of the reasonings of a special science, for that of course must presuppose the general laws and the criterion. ”

“ Let us see how, in these special classes of cases, we shall succeed in verifying the natural presupposition of common sense, which regards error as possible only when our object is not wholly present to mind, and which assumes that a judgment can have an object that is yet only partially present to mind. In choosing the classes of cases, we shall first follow common sense as to their definition. We shall take just the assumptions of daily life, and shall show that they lead us into difficulty. We are not for the first bound to explain why these assumptions are made. ”