Charles Sanders Peirce Quotes & Sayings

My language is the sum total of myself. — Charles Sanders Peirce

Bad reasoning as well as good reasoning is possible; and this fact is the foundation of the practical side of logic. — Charles Sanders Peirce

All the evolution we know of proceeds from the vague to the definite. — Charles Sanders Peirce

We shall do better to abandon the whole attempt to learn the truthunless we can trust to the human mind's having such a powerof guessing right that before very many hypotheses shall have been tried, intelligent guessing may be expected to lead us to one which will support all tests, leaving the vast majority of possible hypotheses unexamined. — Charles Sanders Peirce

It is not too much to say that next after the passion to learn there is no quality so indispensable to the successful prosecutionof science as imagination. Find me a people whose early medicine is not mixed up with magic and incantations, and I will find you a people devoid of all scientific ability. — Charles Sanders Peirce

Let us not pretend to doubt in philosophy what we do not doubt in our hearts. — Charles Sanders Peirce

Mere imagination would indeed be mere trifling; only no imagination is mere . — Charles Sanders Peirce

And what, then, is belief? It is the demi-cadence which closes a musical phrase in the symphony of our intellectual life. — Charles Sanders Peirce

Mathematics is distinguished from all other sciences except only ethics, in standing in no need of ethics. Every other science, even logic, especially in its early stages, is in danger of evaporating into airy nothingness, degenerating, as the Germans say, into an arachnoid film, spun from the stuff that dreams are made of. There is no such danger for pure mathematics; for that is precisely what mathematics ought to be. — Charles Sanders Peirce

It is the man of science, eager to have his every opinion regenerated, his every idea rationalized, by drinking at the fountain of fact, and devoting all the energies of his life to the cult of truth, not as he understands it, but as he does not yet understand it, that ought properly to be called a philosopher. — Charles Sanders Peirce

Notwithstanding all that has been discovered since Newton's time, his saying that we are little children picking up pretty pebbles on the beach while the whole ocean lies before us unexplored remains substantially as true as ever, and will do so though we shovel up the pebbles by steam shovels and carry them off in carloads. — Charles Sanders Peirce

There is not a single truth of science upon which we ought to bet more than about a million of millions to one. — Charles Sanders Peirce

For example, there are numbers of chemists who occupy themselves exclusively with the study of dyestuffs. They discover facts that are useful to scientific chemistry; but they do not rank as genuine scientific men. The genuine scientific chemist cares just as much to learn about erbium-the extreme rarity of which renders it commercially unimportant-as he does about iron. He is more eager to learn about erbium if the knowledge of it would do more to complete his conception of the Periodic Law, which expresses the mutual relations of the elements. — Charles Sanders Peirce

The pragmatist knows that doubt is an art which hs to be acquired with difficulty. — Charles Sanders Peirce

This branch of mathematics [Probability] is the only one, I believe, in which good writers frequently get results which are entirely erroneous. — Charles Sanders Peirce

The method of authority will always govern the mass of mankind; and those who wield the various forms of organized force in the state will never be convinced that dangerous reasoning ought not to be suppressed in some way. — Charles Sanders Peirce

Every new concept first comes to the mind in a judgment. — Charles Sanders Peirce

It is impossible not to envy the man who can dismiss reason, although we know how it must turn out at last. — Charles Sanders Peirce

Generality is, indeed, an indispensable ingredient of reality; for mere individual existence or actuality without any regularity whatever is a nullity. Chaos is pure nothing. — Charles Sanders Peirce

Our whole past experience is continually in our consciousness, though most of it sunk to a great depth of dimness. I think of consciousness as a bottomless lake, whose waters seem transparent, yet into which we can clearly see but a little way. — Charles Sanders Peirce

We start, then, with nothing, pure zero. But this is not the nothing of negation. For not means other than, and other is merely a synonym of the ordinal numeral second. As such it implies a first; while the present pure zero is prior to every first. The nothing of negation is the nothing of death, which comes second to, or after, everything. But this pure zero is the nothing of not having been born. There is no individual thing, no compulsion, outward nor inward, no law. It is the germinal nothing, in which the whole universe is involved or foreshadowed. As such, it is absolutely undefined and unlimited possibility
boundless possibility. There is no compulsion and no law. It is boundless freedom. — Charles Sanders Peirce

If an opinion can eventually go to the determination of a practical belief, it, in so far, becomes itself a practical belief; and every proposition that is not pure metaphysical jargon and chatter must have some possible bearing upon practice. — Charles Sanders Peirce

The a priori method is distinguished for its comfortable conclusions. It is the nature of the process to adopt whatever belief weare inclined to, and there are certain flatteries to the vanity of man which we all believe by nature, until we are awakened from our pleasing dream by rough facts. — Charles Sanders Peirce

The difference between a pessimistic and an optimistic mind is of such controlling importance in regard to every intellectual function, and especially for the conduct of life, that it is out of the question to admit that both are normal, and the great majority of mankind are naturally optimistic. — Charles Sanders Peirce

Law is par excellence the thing that wants a reason. Now the only possible way of accounting for the laws of nature, and for uniformity in general, is to suppose them results of evolution. — Charles Sanders Peirce

Some think to avoid the influence of metaphysical errors, by paying no attention to metaphysics; but experience shows that these men beyond all others are held in an iron vice of metaphysical theory, because by theories that they have never called in question. — Charles Sanders Peirce

The truth is, that common-sense, or thought as it first emerges above the level of the narrowly practical, is deeply imbued with that bad logical quality to which the epithet metaphysical is commonly applied; and nothing can clear it up but a severe course of logic. — Charles Sanders Peirce

We may say that feelings have two kinds of intensity. One is the intensity of the feeling itself, by which loud sounds are distinguished from faint ones, luminous colors from dark ones, highly chromatic colors from almost neutral tints, etc. The other is the intensity of consciousness that lays hold of the feeling, which makes the ticking of a watch actually heard infinitely more vivid than a cannon shot remembered to have been heard a few minutes ago. — Charles Sanders Peirce

A quality is something capable of being completely embodied. A law never can be embodied in its character as a law except by determining a habit. A quality is how something may or might have been. A law is how an endless future must continue to be. — Charles Sanders Peirce

The idea does not belong to the soul; it is the soul that belongs to the idea. — Charles Sanders Peirce

All the progress we have made in philosophy ... is the result of that methodical skepticism which is the element of human freedom. — Charles Sanders Peirce

We cannot begin with complete doubt. — Charles Sanders Peirce

Every work of science great enough to be well remembered for a few generations affords some exemplification of the defective state of the art of reasoning of the time when it was written; and each chief step in science has been a lesson in logic. — Charles Sanders Peirce

There never was a sounder logical maxim of scientific procedure than Ockham's razor: Entia non sunt multiplicanda praeter necessitatem. That is to say; before you try a complicated hypothesis, you should make quite sure that no simplification of it will explain the facts equally well. — Charles Sanders Peirce

There is a kink in my damned brain that prevents me from thinking as other people think. — Charles Sanders Peirce

We think only in signs. — Charles Sanders Peirce

A pair of statements may be taken conjunctively or disjunctively; for example, "It lightens and it thunders ," is conjunctive, "It lightens or it thunders" is disjunctive. Each such individual act of connecting a pair of statements is a new monad for the mathematician . — Charles Sanders Peirce

Over against any cognition, there is an unknown but knowable reality; but over against all possible cognition, there is only the self-contradictory. In short, cognizability (in its widest sense) and being are not merely metaphysically the same, but are synonymous terms. — Charles Sanders Peirce

If we are to define science, ... it does not consist so much in knowing, nor even in "organized knowledge," as it does in diligent inquiry into truth for truth's sake, without any sort of axe to grind, nor for the sake of the delight of contemplating it, but from an impulse to penetrate into the reason of things. — Charles Sanders Peirce

By an object, I mean anything that we can think, i.e. anything we can talk about. — Charles Sanders Peirce

The entire universe is perfused with signs, if it is not composed exclusively of signs. — Charles Sanders Peirce

Unless man have a natural bent in accordance with nature's, he has no chance of understanding nature at all. — Charles Sanders Peirce

The opinion which is fated to be ultimately agreed to by all who investigate, is what we mean by the truth, and the object represented in this opinion is the real. That is the way I would explain reality. — Charles Sanders Peirce

Truly, that reason upon which we plume ourselves, though it may answer for little things, yet for great decisions is hardly surer than a toss up. — Charles Sanders Peirce

The final upshot of thinking is the exercise of volition, and of this thought no longer forms a part; but belief is only a stadium of mental action, an effect upon our nature due to thought, which will influence future thinking. — Charles Sanders Peirce

In all the works on pedagogy that ever I read - and they have been many, big, and heavy - I don't remember that any one has advocated a system of teaching by practical jokes, mostly cruel. That, however, describes the method of our great teacher, Experience. — Charles Sanders Peirce

Third, consider the insistency of an idea. The insistency of a past idea with reference to the present is a quantity which is less, the further back that past idea is, and rises to infinity as the past idea is brought up into coincidence with the present. — Charles Sanders Peirce

No general description of the mode of advance of human knowledge can be just which leaves out of account the social aspect of knowledge. That is of its very essence. What a thing society is! The workingman, with his trade union, knows that. Men and women moving in polite society understand it, still better. But Bohemians, like me, whose work is done in solitude, are apt to forget that not only is a man as a whole little better than a brute in solitude, but also that everything that bears any important meaning to him must receive its interpretation from social considerations. — Charles Sanders Peirce

Let it be considered that what is more wholesome than any particular belief is integrity of belief; and that to avoid looking into the support of any belief from a fear that it may turn out rotten is quite as immoral as it is disadvantageous. — Charles Sanders Peirce

The essence of belief is the establishment of a habit; and different beliefs are distinguished by the different modes of action to which they give rise. — Charles Sanders Peirce

It will sometimes strike a scientific man that the philosophers have been less intent on finding out what the facts are, than on inquiring what belief is most in harmony with their system. — Charles Sanders Peirce

All the followers of science are fully persuaded that the processes of investigation, if only pushed far enough, will give one certain solution to each question to which they can be applied ... This great law is embodied in the conception of truth and reality. The opinion which is fated to be ultimately agreed to by all who investigate is what we mean by the truth, and the object represented in this opinion is the real. — Charles Sanders Peirce

It is ... easy to be certain. One has only to be sufficiently vague. — Charles Sanders Peirce

All the greatest achievements of mind have been beyond the power of unaided individuals. — Charles Sanders Peirce

Upon this first, and in one sense this sole, rule of reason, that in order to learn you must desire to learn, and in so desiring not be satisfied with what you already incline to think, there follows one corollary which itself deserves to be inscribed upon every wall of the city of philosophy: Do not block the way of inquiry. — Charles Sanders Peirce

One will meet, for example, the virtual assumption that what is relative to thought cannot be real. But why not, exactly? Red is relative to sight, but the fact that this or that is in that relation to vision that we call being red is not itself relative to sight; it is a real fact. — Charles Sanders Peirce

Doubt is an uneasy and dissatisfied state from which we struggle to free ourselves and pass into the state of belief; while the latter is a calm and satisfactory state which we do not wish to avoid, or to change to a belief in anything else. — Charles Sanders Peirce

A sign, or representamen, is something which stands to somebody for something in some respect or capacity. It addresses somebody,that is, creates in the mind of that person an equivalent sign, or perhaps a more developed sign. That sign which it creates I call the interpretant of the first sign. The sign stands for something, its object. It stands for that object, not in all respects, but in reference to a sort of idea, which I have sometimes called the ground of the representamen. — Charles Sanders Peirce

The real, then, is that which, sooner or later, information and reasoning would finally result in, and which is therefore independent of the vagaries of me and you. Thus, the very origin of the conception of reality shows that this conception essentially involves the notion of a COMMUNITY, without definite limits, and capable of a definite increase of knowledge. — Charles Sanders Peirce

The universe ought to be presumed too vast to have any character. — Charles Sanders Peirce

When an image is said to be singular, it is meant that it is absolutely determinate in all respects. Every possible character, or the negative thereof, must be true of such an image. — Charles Sanders Peirce

All human affairs rest upon probabilities, and the same thing is true everywhere. If man were immortal he could be perfectly sure of seeing the day when everything in which he had trusted would betray his trust, and, in short, of coming eventually to hopeless misery. He would break down, at last, as every great fortune, as every dynasty, as every civilization does. In place of this we have death. — Charles Sanders Peirce

It is certain that the only hope of retroductive reasoning ever reaching the truth is that there may be some natural tendency toward an agreement between the ideas which suggest themselves to the human mind and those which are concerned in the laws of nature. — Charles Sanders Peirce

We do not really think, we are barely conscious, until something goes wrong. — Charles Sanders Peirce

The woof and warp of all thought and all research is symbols, and the life of thought and science is the life inherent in symbols; so that it is wrong to say that a good language is important to good thought, merely; for it is the essence of it. — Charles Sanders Peirce

When anything is present to the mind, what is the very first and simplest character to be noted in it, in every case, no matter how little elevated the object may be? Certainly, it is its presentness . — Charles Sanders Peirce

It is a common observation that a science first begins to be exact when it is quantitatively treated. What are called the exact sciences are no others than the mathematical ones. — Charles Sanders Peirce

Mathematics is purely hypothetical: it produces nothing but conditional propositions. — Charles Sanders Peirce

The definition of definition is at bottom just what the maxim of pragmatism expresses. — Charles Sanders Peirce

True science is distinctively the study of useless things. For the useful things will get studied without the aid of scientific men. To employ these rare minds on such work is like running a steam engine by burning diamonds. — Charles Sanders Peirce

The percept is the reality. It is not in propositional form. But the most immediate judgment concerning it is abstract. It is therefore essentially unlike the reality, although it must be accepted as true to that reality. Its truth consists in the fact that it is impossible to correct it, and in the fact that it only professes to consider one aspect of the percept. — Charles Sanders Peirce

[For] men to whom nothing seems great but reason ... nature ... is a cosmos, so admirable, that to penetrate to its ways seems to them the only thing that makes life worth living. These are the men whom we see possessed by a passion to learn ... Those are the natural scientific men; and they are the only men that have any real success in scientific research. — Charles Sanders Peirce

Consider what effects that might conceivably have practical bearings you conceive the objects of your conception to have. Then, your conception of those effects is the whole of your conception of the object. — Charles Sanders Peirce

Another characteristic of mathematical thought is that it can have no success where it cannot generalize. — Charles Sanders Peirce

Three elements go to make up an idea. The first is its intrinsic quality as a feeling. The second is the energy with which it affects other ideas, an energy which is infinite in the here-and-nowness of immediate sensation, finite and relative in the recency of the past. The third element is the tendency of an idea to bring along other ideas with it. — Charles Sanders Peirce

It is terrible to see how a single unclear idea, a single formula without meaning, lurking in a young man's head, will sometimes act like an obstruction of inert matter in an artery, hindering the nutrition of the brain and condemning its victim to pine away in the fullness of his intellectual vigor and in the midst of intellectual plenty. — Charles Sanders Peirce

Whenever a man acts purposively, he acts under a belief in some experimental phenomenon. Consequently, the sum of the experimental phenomena that a proposition implies makes up its entire bearing upon human conduct. — Charles Sanders Peirce

To know what we think, to be masters of our own meaning, will make a solid foundation for great and weighty thought. — Charles Sanders Peirce

Theoretically, I grant you, there is no possibility of error in necessary reasoning. But to speak thus "theoretically," is to uselanguage in a Pickwickian sense. In practice, and in fact, mathematics is not exempt from that liability to error that affects everything that man does. — Charles Sanders Peirce

Fate then is that necessity by which a certain result will surely be brought to pass according to the natural course of events however we may vary the particular circumstances which precede the event. — Charles Sanders Peirce

I think of consciousness as a bottomless lake, whose waters seem transparent, yet into which we can clearly see but a little way.But in this water there are countless objects at different depths; and certain influences will give certain kinds of those objects an upward influence which may be intense enough and continue long enough to bring them into the upper visible layer. After the impulse ceases they commence to sink downwards. — Charles Sanders Peirce

It is not knowing, but the love of learning, that characterizes the scientific man. — Charles Sanders Peirce

Every man is fully satisfied that there is such a thing as truth, or he would not ask any question. — Charles Sanders Peirce

And it is probably that there is some secret here which remains to be discovered. — Charles Sanders Peirce

If liberty of speech is to be untrammeled from the grosser forms of constraint, the uniformity of opinion will be secured by a moral terrorism to which the respectability of society will give its thorough approval. — Charles Sanders Peirce

Looking out of my window this lovely spring morning I see an azalea in full bloom. No, no! I do not see that; though that is the only way I can describe what I see. That is a proposition, a sentence, a fact; but what I perceive is not proposition, sentence, fact, but only an image which I make intelligible in part by means of a statement of fact. This statement is abstract; but what I see is concrete. — Charles Sanders Peirce

Theology, I am persuaded, derives its initial impulse from a religious wavering; for there is quite as much, or more, that is mysterious and calculated to awaken scientific curiosity in the intercourse with God, and it [is] a problem quite analogous to that of theology. — Charles Sanders Peirce

Do you call it doubting to write down on a piece of paper that you doubt? If so, doubt has nothing to do with any serious business. But do not make believe; if pedantry has not eaten all the reality out of you, recognize, as you must, that there is much that you do not doubt, in the least. Now that which you do not at all doubt, you must and do regard as infallible, absolute truth. — Charles Sanders Peirce

Truth is that concordance of an abstract statement with the ideal limit towards which endless investigation would tend to bring scientific belief, which concordance the abstract statement may possess by virtue of the confession of its inaccuracy and one-sidedness, and this confession is an essential ingredient of truth. — Charles Sanders Peirce

It has often been argued that absolute scepticism is self-contradictory; but this is a mistake: and even if it were not so, it would be no argument against the absolute sceptic, inasmuch as he does not admit that no contradictory propositions are true. Indeed, it would be impossible to move such a man, for his scepticism consists in considering every argument and never deciding upon its validity; he would, therefore, act in this way in reference to the arguments brought against him. — Charles Sanders Peirce

We should chiefly depend not upon that department of the soul which is most superficial and fallible (our reason), but upon that department that is deep and sure, which is instinct. — Charles Sanders Peirce

A true proposition is a proposition belief which would never lead to such disappointment so long as the proposition is not understood otherwise than it was intended. — Charles Sanders Peirce

But the extraordinary insight which some persons are able to gain of others from indications so slight that it is difficult to ascertain what they are, is certainly rendered more comprehensible by the view here taken. — Charles Sanders Peirce

We, one and all of us, have an instinct to pray; and this fact constitutes an invitation from God to pray. — Charles Sanders Peirce

Among the minor, yet striking characteristics of mathematics, may be mentioned the fleshless and skeletal build of its propositions; the peculiar difficulty, complication, and stress of its reasonings; the perfect exactitude of its results; their broad universality; their practical infallibility. — Charles Sanders Peirce