On the Correct Roles of Induction and Deduction in Human Life: Two Sentences from Ayn Rand’s Theory of Concepts

Original thinkers often state their identifications succinctly.

Ayn Rand’s notion of measurement omission (Introduction to Objectivist Epistemology, chap. 2) in the formation of concepts is one such identification. Here is another (p. 28):

The process of observing the facts of reality and of integrating them into concepts is, in essence, a process of induction. The process of subsuming new instances under a known concept is, in essence, a process of deduction.

These brief and to the point sentences state not just the two fundamental methods of cognition, but more importantly, the correct roles of induction and deduction in human life.

And by “human life,” I mean science as well as everyday life.

Induction is the process of generalization, of forming universal concepts based on our observation of particular objects or events. The definition of a single concept states a principle—all humans possess the capacity to reason, for example—and the combination of several or many concepts and principles builds our knowledge of reality and, in some cases, establishes the physical, biological, and human sciences.

Induction is conceptualization. From an early age, probably before we can assign words to them, we all practice the inductive formation of universal concepts.

This was my example in an earlier post of our daughter, before she could walk or talk, laughing heartily at her first sight of a bouncing ball (Applying Principles, pp. 322-24). She identified a universal, because her mind, to quote Aristotle (Posterior Analytics, 100a13), “is so constituted as to be capable of this process” (though the universal is not “in the thing,” as Aristotle assumed).

Rand’s identification describes in general terms the true nature of induction and makes the biological and human sciences as exact and valid as the physical sciences.*

Deduction is the process of identifying particular objects or events as instances of the general knowledge we have already acquired. The process, more accurately, is one of application.

Deduction is what Sherlock Holmes did and what medical doctors do, and what we all do in our everyday lives. We apply general knowledge to specific cases to guide us in making choices and taking actions.

Technology and the applied sciences are sciences of method and therefore are largely deductive, deriving their basic principles from the more fundamental sciences on which they rest, for example, engineering from physics and chemistry, medicine from biology, and economics from psychology with several business disciplines drawing their basic principles from both psychology and economics.

This identification of deduction as application dispenses with the detached-from-reality deduction for the sake of deduction that has dominated the academic world since the Middle Ages. Deduction as application demonstrates how much deduction we practice in our everyday lives.

We all induce and deduce—some of us better (more accurately) and at greater length (in intensive study) than others. What Ayn Rand’s identifications mean is that induction and deduction are not a monopoly of scientists, philosophers, or academics in general.

Where then does measurement fit in the sciences? Conceptualization is universalization, which means its essence is measurement omission, which means the essence of theoretical science is measurement omission. This means that measurement is an aid to theoretical science, not its essence.

Measurement is crucial in the applied physical sciences when, for example, we want to send astronauts to the moon and back. Measurement in the biological and human sciences, however, is not quantitatively exact in the sense of constructing advanced mathematical equations to predict the behavior of animals or humans.

In the human sciences it is that annoying thing called free will—annoying to many human scientists, most of whom are materialists and determinists—that prevents the human scientists’ “elegant” equations from making any practical sense, or from being replicated in subsequent studies.**

The biological and human sciences are exact and valid, if the conceptualizations made by the scientists working in those fields have correctly identified the aspect of reality they are studying. The identifications are not equations, but they are quantitative. For example, psychological depression can be severe or mild.

“Measurement omission” does not mean that conceptualization ignores measurements. One individual case is quantitatively distinct from the next one, as two balls can be two different sizes and can be made of different materials.

Precise measurement is what technology and applied science, especially in the physical sciences, must critically pay attention to. Measurement in the applied biological and human sciences does not have to be so precise—because it cannot be.

“Truth,” to quote another succinct identification of Ayn Rand (Objectivist Epistemology, p. 48), “is the product of the recognition (i.e., the identification) of the facts of reality.” Truth, for Rand, is not a correspondence theory, but one that identifies facts. It is a recognition or identification theory.

And what is our guide to truth? Logic, of course, as “the art of non-contradictory identification” (Objectivist Epistemology, p. 36), not the mathematical or symbolic stuff that is taught in universities today or the medieval rationalism that permeates the older logic textbooks.

Induction and deduction are what we all use every day in our practical lives.

Induction and deduction, respectively, are conceptualization and application. Measurement is an important component of the two, but it is not their essence.


* See John P. McCaskey, “Induction in the Socratic Tradition,” in Shifting the Paradigm: Alternative Perspectives on Induction, ed. Louis F. Groarke & Paolo C. Biondi (Berlin: De Gruyter, 2014), 161–192, on his efforts to revive Socratic induction, a tradition promoted and debated both before and after Francis Bacon, but eventually overtaken by the nineteenth-century positivistic, Millian hypothetico-deductive method, a form of rationalistic, propositional inference. Socratic induction—generalization from particular things or concretes to universal abstract ideas—is consistent with Ayn Rand’s epistemology as inductive concept formation through measurement omission.

** “Man is that which fits economic equations,” as Ayn Rand (Capitalism: The Unknown Ideal, p. 7) so simply and aptly caricatured the very rationalistic, pseudo-deductive doctrine of pure and perfect competition in economics.

Independence and Certainty

In our age of post-Kantian skepticism and relativism, it follows, according to the skeptics and relativists, that anyone claiming epistemological or ethical certainty is either a deluded fundamentalist or a wannabe or actual dictator.

Inquisitors and jihadis are certain of their convictions and maim and kill those who do not agree with them. Hitler was certain and viciously imposed his will on his own citizens and the world and, of course, the Jewish people. The implication is that Inquisitors, jihadis, and Hitlers are selfish, independent personalities.

The argument often does not go this far, though it is implied, and some, including Holocaust scholars, have said as much.* After all, this train of thought continues, no one is omniscient, and because of our inherent fallibility, we must allow freedom of speech. This is what makes a society free.

Lack of omniscience means inability to be certain, which means we must invite and relish criticism to clarify our thoughts, and perhaps gradually get closer and closer to the truth, though absolute truth can never be attained.

This is what logical positivism and its offspring have taught us. Claims of certainty are dangerous. We have to talk things over and aim for consensus, sometimes through voting. This in essence is the epistemological justification of democracy.**

In other words, anyone who believes in absolutes believes in absolute authority. The independent personality is one who asserts facts as absolutely true, and that is what is dangerous.

So does this mean the boy in the story of the Emperor’s New Clothes should request a vote before speaking up, assuming the emperor is tolerant of critics(!)? In addition to the self-contradictions of skepticism and relativism, this question is a reductio ad absurdum.***

It does not follow from human fallibility that absolute certainty is authoritarian or that strong, independent personalities are actual or wannabe dictators. Nor is the argument from fallibility the fundamental defense of freedom of speech and the free society.

In a single sentence, the answer to the issue is a sound, objective theory of universals that allows the identification of sound, objective values, which in turn defines social relationships in terms of individual rights, that is, freedoms to take action without coercion, including the freedom to express oneself on one’s own property or on that of someone else with whom one has contracted to make that expression.

Freedom of speech presupposes property rights, and democracy, if it is not to be a form of dictatorship—democracy, remember, killed Socrates—presupposes and is restrained by all individual rights, which therefore means democracy in a free society is demoted to the relatively minor function of selecting our leaders, along with other non-rights-violating details.

Democracy is not the arbiter of truth (or “approximate” truth) or of ethical or legal behavior.

The sound theory of universals is Ayn Rand’s (1; Applying Principles, pp. 322-24). It is a theory based on the contextual nature of knowledge that allows certain truth to be asserted as absolute within a specified context. Because knowledge grows over time, adjustments to earlier absolute certainties may have to be made, as Newton’s theories were adjusted by Einstein’s.

Incidentally, something over the years must have been right, true, and certain about Newton’s and Einstein’s ideas, because in the use of both theories, spaceships have gone to the moon and back.

Truth and certainty—by peaceful, independent-minded, non-authoritarian scientists—do seem possible.

Yes, we are fallible and not omniscient, which means we must submit our expressions to evaluation and criticism and be prepared to defend them, but this is not a justification of freedom of speech.

In order to survive and flourish, humans must exercise their inborn, volitional capacity to reason. Because this exercise of reason is not activated by our genes or environment (Applying Principles, pp. 315-18), we must be left free to choose—that is, it is right or moral for us to be free from the coercion of others, especially the government—to allow each of us as individuals to generate and sustain action to achieve our chosen values. Trade is our means of social cooperation.

The source and justification of individual rights is our nature as rational beings. It is right and moral to be free of any initiation against us of the use of physical force.

Thus, whatever we say or write, either on our own property or on that of the others cooperating with us, is, at least sometimes, an assertion of truth and certainty. It is right and moral for us to make these assertions, first, because our freedom of expression is consonant with and required by our human nature and, second, because our speech, writing, and expressions derive from our rights to life, liberty and property.

Inquisitors, jihadis, and Hitlers of the world, in contrast, do also make assertions of truth and certainty, but they back up their assertions with a gun. Their expressions are not open to evaluation and criticism because they tolerate no disagreement.

They are the authoritarians, the dictators, who at root, as Stanton Samenow demonstrates, are criminal personalities. As liars and cheaters, they are not the least bit interested in perceiving and asserting facts as facts. They most certainly are not independent personalities; they are among the worst of the dependent.

Brandishing and using guns, as they do, is anathema to our rational nature. Their goals and accomplishments are to silence our reason. Their “truth” and “certainty” lead to wanton destruction of humankind and civilization.

Talking and voting does not make any individual more or less independent, and it is not the means of preventing another Holocaust. Lack of certainty may indicate insecurity or insufficient knowledge to make a decision with confidence.

To link certainty to dictatorship is the red herring of all red herrings, brought to us by post-Kantian agnosticism, both in epistemology and ethics.

It is time to restore certainty to its proper place in knowledge and values.


* Years ago, I heard a Holocaust scholar say that the Nazis were certain of their convictions; therefore, it is good that we not be.

** The argument is John Stuart Mill’s utilitarian defense of free speech, restated in Jonathan Rauch, Kindly Inquisitors: The New Attacks on Free Thought. Rauch in 1993 was responding to an early wave of censorship by political correctness.

*** Here are the self-contradictions: skeptics assert as an absolute certainty that certainty is impossible and the relativists claim absolutely that all claims are relative. Cratylus, the Greek skeptic who stopped talking, is another reductio.