Digital Companion to C. S. Peirce
1868 | Some Consequences of Four Incapacities | CP 5.311-312

… And what do we mean by the real? It is a conception which we must first have had when we discovered that there was an unreal, an illusion; that is, when we first corrected ourselves. Now the distinction for which alone this fact logically called, was between an ens relative to private inward determinations, to the negations belonging to idiosyncrasy, and an ens such as would stand in the long run. 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. And so those two series of cognition – the real and the unreal – consist of those which, at a time sufficiently future, the community will always continue to re-affirm; and of those which, under the same conditions, will ever after be denied. Now, a proposition whose falsity can never be discovered, and the error of which therefore is absolutely incognizable, contains, upon our principle, absolutely no error. Consequently, that which is thought in these cognitions is the real, as it really is. There is nothing, then, to prevent our knowing outward things as they really are, and it is most likely that we do thus know them in numberless cases, although we can never be absolutely certain of doing so in any special case.

But it follows that since no cognition of ours is absolutely determinate, generals must have a real existence. Now this scholastic realism is usually set down as a belief in metaphysical fictions. But, in fact, a realist is simply one who knows no more recondite reality than that which is represented in a true representation.

1870 | Notes for Lectures on Logic to be given 1st term 1870-71 | W 2:439-40

A real thing is something whose characters are independent of how any representation represents it to be.

Independent, therefore, of how any number of men think it to be. Idealism does not falsify definition.


The Real thing is the ultimate opinion about it.

About it that is about the ultimate opinion, but not involving the reflection that the opinion is itself that ultimate one and is the real thing. Indeed this opinion is in one sense an ideal inasmuch as more experience and reasoning may always be had.

1871 | Fraser's The Works of George Berkeley | CP 8.12

… Objects are divided into figments, dreams, etc., on the one hand, and realities on the other. The former are those which exist only inasmuch as you or I or some man imagines them; the latter are those which have an existence independent of your mind or mine or that of any number of persons. The real is that which is not whatever we happen to think it, but is unaffected by what we may think of it. [—] Where is the real, the thing independent of how we think it, to be found? There must be such a thing, for we find our opinions constrained; there is something, therefore, which influences our thoughts, and is not created by them. We have, it is true, nothing immediately present to us but thoughts. These thoughts, however, have been caused by sensations, and those sensations are constrained by something out of the mind. This thing out of the mind, which directly influences sensation, and through sensation thought, because it is out of the mind, is independent of how we think it, and is, in short, the real. Here is one view of reality, a very familiar one. And from this point of view it is clear that the nominalistic answer must be given to the question concerning universals. [—] This conception of reality is so familiar, that it is unnecessary to dwell upon it; but the other, or realist conception, if less familiar, is even more natural and obvious. All human thought and opinion contains an arbitrary, accidental element, dependent on the limitations in circumstances, power, and bent of the individual; an element of error, in short. But human opinion universally tends in the long run to a definite form, which is the truth. Let any human being have enough information and exert enough thought upon any question, and the result will be that he will arrive at a certain definite conclusion, which is the same that any other mind will reach under sufficiently favorable circumstances. [—] There is, then, to every question a true answer, a final conclusion, to which the opinion of every man is constantly gravitating. He may for a time recede from it, but give him more experience and time for consideration, and he will finally approach it. The individual may not live to reach the truth; there is a residuum of error in every individual’s opinions. No matter; it remains that there is a definite opinion to which the mind of man is, on the whole and in the long run, tending. On many questions the final agreement is already reached, on all it will be reached if time enough is given. The arbitrary will or other individual peculiarities of a sufficiently large number of minds may postpone the general agreement in that opinion indefinitely; but it cannot affect what the character of that opinion shall be when it is reached. This final opinion, then, is independent, not indeed of thought in general, but of all that is arbitrary and individual in thought; is quite independent of how you, or I, or any number of men think. Everything, therefore, which will be thought to exist in the final opinion is real, and nothing else.

1872 | Chapter IV. Of Reality | W 3:58

If an object is of whatever character I or any man or men will have it to be or imagine it, it is a fiction; but if its characters are independent of what you or I or any number of men think about it, it is a reality. The object of that final settled opinion to which it is supposed that an investigation will lead, if carried far enough, satisfies this definition of reality; for though the perversity of generations of men may postpone the agreement indefinitely, yet it cannot alter the character of the belief which alone can be permanently established.

1878 | How to Make Our Ideas Clear | CP 5.405-408

Let us now approach the subject of logic, and consider a conception which particularly concerns it, that of reality. Taking clearness in the sense of familiarity, no idea could be clearer than this. Every child uses it with perfect confidence, never dreaming that he does not understand it. As for clearness in its second grade, however, it would probably puzzle most men, even among those of a reflective turn of mind, to give an abstract definition of the real. Yet such a definition may perhaps be reached by considering the points of difference between reality and its opposite, fiction. A figment is a product of somebody’s imagination; it has such characters as his thought impresses upon it. That those characters are independent of how you or I think is an external reality. There are, however, phenomena within our own minds, dependent upon our thought, which are at the same time real in the sense that we really think them. But though their characters depend on how we think, they do not depend on what we think those characters to be. Thus, a dream has a real existence as a mental phenomenon, if somebody has really dreamt it; that he dreamt so and so, does not depend on what anybody thinks was dreamt, but is completely independent of all opinion on the subject. On the other hand, considering, not the fact of dreaming, but the thing dreamt, it retains its peculiarities by virtue of no other fact than that it was dreamt to possess them. Thus we may define the real as that whose characters are independent of what anybody may think them to be.

But, however satisfactory such a definition may be found, it would be a great mistake to suppose that it makes the idea of reality perfectly clear. [—]

On the other hand, all the followers of science are animated by a cheerful hope that the processes of investigation, if only pushed far enough, will give one certain solution to each question to which they apply it. [—] This activity of thought by which we are carried, not where we wish, but to a fore-ordained goal, is like the operation of destiny. No modification of the point of view taken, no selection of other facts for study, no natural bent of mind even, can enable a man to escape the predestinate opinion. This great hope 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. That is the way I would explain reality.

But it may be said that this view is directly opposed to the abstract definition which we have given of reality, inasmuch as it makes the characters of the real depend on what is ultimately thought about them. But the answer to this is that, on the one hand, reality is independent, not necessarily of thought in general, but only of what you or I or any finite number of men may think about it; and that, on the other hand, though the object of the final opinion depends on what that opinion is, yet what that opinion is does not depend on what you or I or any man thinks.

1893 | Grand Logic 1893: Division III. Substantial Study of Logic Chapter VI. The Essence of Reasoning | MS [R] 408:146-7

The commodious and compact representation in our minds, or icon of our hopes about beliefs[,] is that there is something fixed and not subject to our wills called the reality, and that our beliefs come to shape themselves more and more under experience in conformity to that reality. So far as they accord with it we call them true. This is a handy ideal –. this of reality; – but it represents nothing but a hope. We have no warrant for averring that belief of all kinds will get more and more fixed until its variations become indefinitely small. We simply try to fix belief, and trying to do anything implies a hope that we shall to some extent succeed. The pretense of some philosophers that there is any justification for a broader “presupposition” that that is unfounded.

1900-12-23 | Letters to Georg Cantor | NEM 3:773

By a true proposition (if there be any such thing) I mean a proposition which at some time, past or future, emerges into thought, and has the following three characters:

1st, no direct effort of yours, mine, or anybody’s, can reverse it permanently, or even permanently prevent its asserting itself;

2nd, no reasoning or discussion can permanently prevent its asserting itself;

3rd, any prediction based on the proposition, as to what ought to present itself in experience under certain conditions, will be fulfilled when those conditions are satisfied.

By a reality, I mean anything represented in a true proposition.

By a positive reality or truth, I mean one to which all three of the above criteria can be applied, - of course imperfectly, since we can never carry them out to the end.

By an ideal reality or truth, I mean one to which the first two criteria can be applied imperfectly, but the third not at all, since the proposition does not imply that any particular state of things will ever appear in experience. Such is a truth of pure mathematics.

By an ultimate reality or truth, I mean one to which the first criterion can be in some measure applied, but which can never be overthrown or rendered clearer by any reasoning, and upon which alone no predictions can be based. Thus, if you are kicked by a horse, the fact of the pain is beyond all discussion and far less can it be shaken or established by any experimentation.

1902 | Truth and Falsity and Error | CP 5.567

These characters equally apply to pure mathematics. [—] The pure mathematician deals exclusively with hypotheses. Whether or not there is any corresponding real thing, he does not care. His hypotheses are creatures of his own imagination; but he discovers in them relations which surprise him sometimes. A metaphysician may hold that this very forcing upon the mathematician’s acceptance of propositions for which he was not prepared, proves, or even constitutes, a mode of being independent of the mathematician’s thought, and so a reality. But whether there is any reality or not, the truth of the pure mathematical proposition is constituted by the impossibility of ever finding a case in which it fails.

1902 | Minute Logic: Chapter IV. Ethics (Logic IV) | CP 6.349

Reality […] is a special mode of being, the characteristic of which is that things that are real are whatever they really are, independently of any assertion about them.

1902 | Truth and Falsity and Error | CP 5.565-566

Truth is a character which attaches to an abstract proposition, such as a person might utter. [—] But whether or not there would be perhaps any reality is a question for the metaphysician, not the logician. Even if the metaphysician decides that where there is no truth there is no reality, still the distinction between the character of truth and the character of reality is plain and definable. 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. A further explanation of what this concordance consists in will be given below. Reality is that mode of being by virtue of which the real thing is as it is, irrespectively of what any mind or any definite collection of minds may represent it to be. The truth of the proposition that Caesar crossed the Rubicon consists in the fact that the further we push our archaeological and other studies, the more strongly will that conclusion force itself on our minds forever – or would do so, if study were to go on forever. An idealist metaphysician may hold that therein also lies the whole reality behind the proposition; for though men may for a time persuade themselves that Caesar did not cross the Rubicon, and may contrive to render this belief universal for any number of generations, yet ultimately research – if it be persisted in – must bring back the contrary belief. But in holding that doctrine, the idealist necessarily draws the distinction between truth and reality.

In the above we have considered positive scientific truth. But the same definitions equally hold in the normative sciences. If a moralist describes an ideal as the summum bonum, in the first place, the perfect truth of his statement requires that it should involve the confession that the perfect doctrine can neither be stated nor conceived. If, with that allowance, the future development of man’s moral nature will only lead to a firmer satisfaction with the described ideal, the doctrine is true. A metaphysician may hold that the fact that the ideal thus forces itself upon the mind, so that minds in their development cannot fail to come to accept it, argues that the ideal is real: he may even hold that that fact (if it be one) constitutes a reality. But the two ideas, truth and reality, are distinguished here by the same characters given in the above definitions.

1902-03 [c.] | Reason's Rules | MS [R] 596:13-14

[The] real state of things is something which is “so,” that is, has a certain determination, or specialization, or being, whether it be opined to be so or otherwise. Therefore, the reader holds that for every question not nonsensical, there is a certain determination of being which is completely independent of what you, or I, or any man or generations of men may opine about it.

1903 [c.] | The Theory of Multitude | MS [R] 24:2-3

The reality of a thing consists in its retaining its own characters quite independently of whatever opinion or fancy you or I or any man or generation of men may entertain about it. Reality has its grades. Any object which maintains its characters with sufficient steadiness to make one proposition false and another true has sufficient reality for the purposes of the mathematician.

1904 [c.] | A draft of a review of Herbert Nichols' A Treatise on Cosmology, Vol. 1 [CP] | CP 8.191

The method prescribed in the maxim [of pragmatism] is to trace out in the imagination the conceivable practical consequences, – that is, the consequences for deliberate, self-controlled conduct, – of the affirmation or denial of the concept; and the assertion of the maxim is that herein lies the whole of the purport of the word, the entire concept. [—] This maxim once accepted, – intelligently accepted, in the light of the evidence of its truth, – speedily sweeps all metaphysical rubbish out of one’s house. Each abstraction is either pronounced to be gibberish or is provided with a plain, practical definition. The general leaning of the results is toward what the idealists call the naïve, toward common sense, toward anthropomorphism. Thus, for example, the real becomes that which is such as it is regardless of what you or I or any of our folks may think it to be. The external becomes that element which is such as it is regardless of what somebody thinks, feels, or does, whether about that external object or about anything else. Accordingly, the external is necessarily real, while the real may or may not be external; nor is anything absolutely external nor absolutely devoid of externality. Every assertory proposition refers to something external, and even a dream withstands us sufficiently for one description to be true of it and another not. The existent is that which reacts against other things.

1904-09-28 | Letters to William James | CP 8.284

By mellonization (Gr. μέλλωγ the being about to do, to be, or to suffer) I mean that operation of logic by which what is conceived as having been (which I call conceived as parele’lythose) is conceived as repeated or extended indefinitely into what always will be (or what will some day be, that is, its absence will not always be, which equally involves mellonization, which does not assert anything but is merely a mode of conceiving). The conception of the real is derived by a mellonization of the constraint-side of double-sided consciousness. Therefore to say that it is the world of thought that is real is, when properly understood, to assert emphatically the reality of the public world of the indefinite future as against our past opinions of what it was to be.

1905 | What Pragmatism Is | CP 5.430-432

As to reality, one finds it defined in various ways; but if that principle of terminological ethics that was proposed be accepted, the equivocal language will soon disappear. For realis and realitas are not ancient words. They were invented to be terms of philosophy in the thirteenth century, and the meaning they were intended to express is perfectly clear. That is real which has such and such characters, whether anybody thinks it to have those characters or not. At any rate, that is the sense in which the pragmaticist uses the word. Now, just as conduct controlled by ethical reason tends toward fixing certain habits of conduct, the nature of which (as to illustrate the meaning, peaceable habits and not quarrelsome habits) does not depend upon any accidental circumstances, and in that sense may be said to be destined; so, thought, controlled by a rational experimental logic, tends to the fixation of certain opinions, equally destined, the nature of which will be the same in the end, however the perversity of thought of whole generations may cause the postponement of the ultimate fixation. If this be so, as every man of us virtually assumes that it is, in regard to each matter the truth of which he seriously discusses, then, according to the adopted definition of “real,” the state of things which will be believed in that ultimate opinion is real. But, for the most part, such opinions will be general. Consequently, some general objects are real. (Of course, nobody ever thought that all generals were real; but the scholastics used to assume that generals were real when they had hardly any, or quite no, experiential evidence to support their assumption; and their fault lay just there, and not in holding that generals could be real.) [—]

That which any true proposition asserts is real, in the sense of being as it is regardless of what you or I may think about it. Let this proposition be a general conditional proposition as to the future, and it is a real general such as is calculated really to influence human conduct; and such the pragmaticist holds to be the rational purport of every concept.

1905 | Materials for Monist Article: The Consequences of Pragmaticism. Vols. I and II [R] | MS [R] 288:117

A real is anything that is not affected by men’s cognitions about it.

1905 [c.] | Pragmatism, Prag [R] | CP 5.503

reality means a certain kind of non-dependence upon thought, and so is a cognitionary character, while existence means reaction with the environment, and so is a dynamic character…

1906 [c.] | Answers to Questions about my Belief in God | CP 6.495

The word “reality” […] is used in ordinary parlance in its correct philosophical sense. It is curious that its legal meaning, in which we speak of “real estate,” is the earliest, occurring early in the twelfth century. Albertus Magnus, who, as a high ecclesiastic, must have had to do with such matters, imported it into philosophy. But it did not become at all common until Duns Scotus, in the latter part of the thirteenth century began to use it freely. I define the real as that which holds its characters on such a tenure that it makes not the slightest difference what any man or men may have thought them to be, or ever will have thought them to be, here using thought to include, imagining, opining, and willing (as long as forcible means are not used); but the real thing’s characters will remain absolutely untouched.

1907 | The Fourth Curiosity | CP 6.340

But to say that a singular is known by sense is a confusion of thought. It is not known by the feeling-element of sense, but by the compulsion, the insistency, that characterizes experience. For the singular subject is real; and reality is insistency. That is what we mean by “reality.” It is the brute irrational insistency that forces us to acknowledge the reality of what we experience, that gives us our conviction of any singular.

1908 | A Neglected Argument for the Reality of God | EP 2:434-435; CP 6.453

“Real” is a word invented in the thirteenth century to signify having Properties, i.e. characters sufficing to identify their subject, and possessing these whether they be anywise attributed to it by any single man or group of men, or not. Thus, the substance of a dream is not Real , since it was such as it was, merely in that a dreamer so dreamed it; but the fact of the dream is Real, if it was dreamed; since if so, its date, the name of the dreamer, etc., make up a set of circumstances sufficient to distinguish it from all other events; and these belong to it, i.e., would be true if predicated of it, whether A, B, or C Actually ascertains them or not.

1909 | Letters to Lady Welby | SS 117

That which is such that something true about it is either true independently of the thought of any definite mind or minds or is at least true independently of what any person or any definite individual group of persons think about that truth, is real.

1909 | Preface | MS [R] 634:9-10

Whether the object immediately before the mind is the Real object or not seems to be a question from which it is difficult to extract any clear meaning; but it [is] quite certain that no thinking about it will at all modify the Real object, since this is precisely what is meant by calling it Real. It is sometimes an object shaped by thinking, – of which the last sentence affords an example; but so far as it is Real, it is not modified by thinking about it. Now in thinking, the object before the mind is under the thinker’s control and is always modified by the action of his will. It is therefore not the Real thing, although the Real thing is undoubtedly the object he is thinking about.

1909 | Meaning Preface | MS [R] 637:27-28

That is Real which has characters independently of what contrary or other characters any person or collection of persons may in any sort of idea attribute to it. This is not to say the characters are possessed independently of all Thought about it, nor of whatever might be the final opinion to which sufficient research would lead. Thus the substance of a dream, that is, what is dreamed is not Real, since the object dreamed has only such characters as the mind of the dreamer gives it. But the dream itself is a Real fact, if it has occurred no matter who opines that it has not. A Real object may be External or Internal, i.e. mental, as a dream is. For only that is external whose possession of some character is [not merely] independent of individuals’ opinions, but whose possession of any such Real character is independent of any individuals’ thought about any subject and ideation of every kind.

1909 | Meaning Preface | MS [R] 637:27

…Real is the proper contrary of Illusion, Delusion, or Figment, while to exist means, by virtue of the ex in exsistere, to act upon, to react against, the other things that exist in the psycho-physical universe.

1910 | The Rationale of Reason | MS [R] 659:32-3

that circumstance is Real which is as it is whether one thinks that it is so, or not. That object is Real of which whatever is true or is truly said, is so, whether you or I or any person or persons think that it is so, or not, – unless, indeed, the predicate in question (i.e. that which is said of the object,) be, of its very meaning, dependent upon what one thinks of it.

1910 | The Rationale of Reasoning | MS [R] 663:5-6

I call anything “real” be it anything asserted, or imagined, or conceived, or any element of such assertion, image, or concept, or of whatever other sort it may be, if, and only if, it possesses characters which it would possess, just the same, whether […] you or I, or anybody else, or everybody living during any limits of time, opines, fancies, or otherwise thinks it possesses them, or not. Almost everybody and everything possesses some characters that are not of this description.

1911 | A Sketch of Logical Critics | EP 2:457-458

For what is it for a thing to be Real? [—] To say that a thing is Real is merely to say that such predicates as are true of it, or some of them, are true of it regardless of whatever any actual person or persons might think concerning that truth. Unconditionality in that single respect constitutes what we call Reality. Consequently, any habit, or lasting state that consists in the fact that the subject of it would, under certain conditions, behave in a certain way, is Real, provided this be true whether actual persons think so or not; and it must be admitted to be a Real Habit, even if those conditions never actually do get fulfilled.

1911 | A Logical Critique of Essential Articles of Religious Faith | MS [R] 852:9-11

Now, what precisely do we mean when we assert that any thing is “real”; in other words, what is the character which we mean, or intend to cause the person whom we address to believe, is true of that thing. What we all mean is that there are predicates that are true of that thing, and would be true of it, no matter what [a] determinate person or determinate collection of persons might think or imagine to be false of that thing, in any mode of thinking whatsoever. Of course, whether the thing be real or not, there will be other predicates whose being true of it consists in their being thought to be so; for that is involved in the meaning of some predicates, as when we say that a man is “popular.” But if there be so much as a single predicate whose truth of the thing in question is quite independent of its being thought to be so, there will be many such, and that thing will have the important character we call reality.

1913 | On the Meaning of "Real" [R] | MS [R] 930:24-5

What we can in some measure know is our universe in such a sense that we cannot mean anything of what may be “beyond.” But the Ding and sich is very different from my idea of the Real, which is what I opine, or incline to believe that the men wisest about it will some day come unceasingly (as long as such wise men there be) to opine to be be an element of the truth.

1913 [c.] | Reflexions upon Reasoning | MS [R] 686:1

By “reality” is to be understood that part or ingredient of the being of anything which does not depend upon that thing’s actually being represented.