… I was … much concerned with the problem of dogmatic thinking and its relation to critical thinking. What especially interested me was the idea that dogmatic thinking, which I regarded as prescientific, was a stage that was needed if critical thinking was to be possible. Critical thinking must be the result of dogmatic thinking.
… My main idea in 1919 was this. If somebody proposed a scientific theory he should answer, as Einstein did, the question: “Under what conditions would I admit that my theory is untenable?” In other words, what conceivable facts would I accept as refutations, or falsifications, of my theory?
… But when a little later I tentatively introduced the idea of falsifiability (or testability or refutability) of a theory as a criterion of demarcation, I very soon found that every theory can be “immunized” (this excellent term is due to Hans Albert) against criticism. If we allow such immunization, then every theory becomes unfalsifiable. Thus we must exclude at least some immunization.
On the other hand, I also realized that we must not exclude all immunizations, not even all which introduced ad hoc auxiliary hypotheses. For example, the observed motion of Uranus might have been regarded as a falsification of Newton’s theory. Instead the auxiliary hypothesis of an outer planet was introduced ad hoc, thus immunizing the theory. This turned out to be fortunate; for the auxiliary hypothesis was a testable one, even if difficult to test, and it stood up to tests successfully.
All this shows not only that some degree of dogmatism is fruitful, even in science, but also that logically speaking falsifiability, or testability, cannot be regarded as a very sharp criterion.
… immunization is always possible. But the evasion would usually be dishonest: it would consist, say, in denying that a black swan was a swan, or that it was black; or that a non-Keplerian planet was a planet.
… Konrad Lorenz is the author of a marvelous theory in the field of animal psychology, which he calls “imprinting.” It implies that young animals have an inborn mechanism for jumping to unshakable conclusions.
… The following points about Lorenz’s “imprinting” are important:
(1) It is a process — not the only one — of learning by observation.
(2) The problem solved under the stimulus of the observation is inborn; that is, the gosling is genetically conditioned to look out for its mother: it expects to see its mother.
(3) The theory or expectation which solves the problem is also to some extent inborn, or genetically conditioned: it goes far beyond the actual observation, which merely (so to speak) releases or triggers the adoption of a theory which is largely preformed in the organism.
(4) The learning process is nonrepetitive, though it may take a certain amount of time (a short time), and involve often some activity or “effort” on the part of the organism; it therefore may involve a situation not too far removed from that normally encountered. I shall say of such nonrepetitive learning processes that they are “noninductive,” taking repetition as the characteristic of “induction.” …
(5) The observation itself works only like the turning of a key in a lock. Its role is important, but the highly complex result is almost completely preformed.
(6) Imprinting is an irreversible process of learning; that is, it is not subject to correction or revision.
… Most (or perhaps all) learning processes consist in theory formation; that is, in the formation of expectations. The formation of a theory or conjecture has always a “dogmatic,” and often a “critical,” phase. This dogmatic phase shares, with imprinting, the characteristics (2) to (4), and sometimes also (1) and (5), but not normally (6). The critical phase consists in giving up the dogmatic theory under the pressure of disappointed expectations or refutations, and in trying out other dogmas. I noticed that sometimes the dogma was so strongly entrenched that no disappointment could shake it. It is clear that in this case — though only in this case — dogmatic theory formation comes very close to imprinting, of which (6) is characteristic. However, I was inclined to look on (6) as a kind of neurotic aberration.
… in any case in which the method of trial and error is applied to the solution of such a problem as the problem of adaptation (to a maze, say), the trials are as a rule not determined, or not completely determined, by the problem; nor can they anticipate its (unknown) solution otherwise than by a fortunate accident.
… Yet the trials are not always quite blind to the demands of the problem: the problem often determines the range from which the trials are selected (such as the range of the digits [in solving a math problem]). This is well described by David Katz: “A hungry animal divides the environment into edible and inedible things. An animal in flight sees roads of escape and hiding places.” Moreover, the problem may change somewhat with the successive trials; for example, the range may narrow. But there may also be quite different cases, especially on the human level; cases in which everything depends upon an ability to break through the limits of the assumed range. These cases show that the selection of the range itself may be a trial (an unconscious conjecture), and that critical thinking may consist not only in a rejection of any particular trial or conjecture, but also in a rejection of what may be described as a deeper conjecture — the assumption of the range of ‘all possible trials.’ This, I suggest, is what happens in many cases of ‘creative’ thinking.
What characterizes creative thinking, apart from the intensity of the interest in the problem, seems to me often the ability to break through the limits of the range — or to vary the range — from which a less creative thinker selects his trials. This ability, which clearly is a critical ability, may be described as critical imagination. It is often the result of culture clash, that is, a clash between ideas, or frameworks of ideas. Such a clash may help us to break through the ordinary bounds of our imagination.
… A “trial” or a newly formed “dogma” or a new “expectation” is largely the result of inborn needs that give rise to specific problems. But it is also the result of the inborn need to form expectations (in certain specific fields, which in their turn are related to some other needs); and it may also be partly the result of disappointed earlier expectations. I do not of course deny that there may also be an element of personal ingenuity present in the formation of trials or dogmas, but I think that ingenuity and imagination play their main part in the critical process of error elimination. Most of the great theories which are among the supreme achievements of the human mind are the offspring of earlier dogmas, plus criticism.
… although the theory of a dogmatic phase followed by a critical phase is too simple, it is true that there can be no critical phase without a preceding dogmatic phase, a phase in which something — an expectation, a regularity of behavior — is formed, so that error elimination can begin to work on it.
… [This] led me to see that there is no such thing as an unprejudiced observation. All observation is an activity with an aim (to find, or to check, some regularity which is at least vaguely conjectured); an activity guided by problems, and by the context of expectations (the “horizon of expectations” as I later called it).
… All learning is a modification (it may be a refutation) of some prior knowledge and thus, in the last analysis, of some inborn knowledge.