The difficulties connected with my criterion of demarcation (D) are important, but must not be exaggerated. It is vague, since it is a methodological rule, and since the demarcation between science and nonscience is vague. But it is more than sharp enough to make a distinction between many physical theories on the one hand, and metaphysical theories, such as psychoanalysis, or Marxism (in its present form), on the other. This is, of course, one of my main theses; and nobody who has not understood it can be said to have understood my theory.The situation with Marxism is, incidentally, very different from that with psychoanalysis. Marxism was once a scientific theory: it predicted that capitalism would lead to increasing misery and, through a more or less mild revolution, to socialism; it predicted that this would happen first in the technically highest developed countries; and it predicted that the technical evolution of the 'means of production' would lead to social, political, and ideological developments, rather than the other way round.But the (so-called) socialist revolution came first in one of the technically backward countries. And instead of the means of production producing a new ideology, it was Lenin's and Stalin's ideology that Russia must push forward with its industrialization ('Socialism is dictatorship of the proletariat plus electrification') which promoted the new development of the means of production.Thus one might say that Marxism was once a science, but one which was refuted by some of the facts which happened to clash with its predictions (I have here mentioned just a few of these facts).However, Marxism is no longer a science; for it broke the methodological rule that we must accept falsification, and it immunized itself against the most blatant refutations of its predictions. Ever since then, it can be described only as nonscience—as a metaphysical dream, if you like, married to a cruel reality.Psychoanalysis is a very different case. It is an interesting psychological metaphysics (and no doubt there is some truth in it, as there is so often in metaphysical ideas), but it never was a science. There may be lots of people who are Freudian or Adlerian cases: Freud himself was clearly a Freudian case, and Adler an Adlerian case. But what prevents their theories from being scientific in the sense here described is, very simply, that they do not exclude any physically possible human behaviour. Whatever anybody may do is, in principle, explicable in Freudian or Adlerian terms. (Adler's break with Freud was more Adlerian than Freudian, but Freud never looked on it as a refutation of his theory.)The point is very clear. Neither Freud nor Adler excludes any particular person's acting in any particular way, whatever the outward circumstances. Whether a man sacrificed his life to rescue a drowning, child (a case of sublimation) or whether he murdered the child by drowning him (a case of repression) could not possibly be predicted or excluded by Freud's theory; the theory was compatible with everything that could happen—even without any special immunization treatment.Thus while Marxism became non-scientific by its adoption of an immunizing strategy, psychoanalysis was immune to start with, and remained so. In contrast, most physical theories are pretty free of immunizing tactics and highly falsifiable to start with. As a rule, they exclude an infinity of conceivable possibilities.
Because it begins to seem to me at such times that I am incapable of beginning a life in real life, because it has seemed to me that I have lost all touch, all instinct for the actual, the real; because at last I have cursed myself; because after my fantastic nights I have moments of returning sobriety, which are awful! Meanwhile, you hear the whirl and roar of the crowd in the vortex of life around you; you hear, you see, men living in reality; you see that life for them is not forbidden, that their life does not float away like a dream, like a vision; that their life is being eternally renewed, eternally youthful, and not one hour of it is the same as another; while fancy is so spiritless, monotonous to vulgarity and easily scared, the slave of shadows, of the idea, the slave of the first cloud that shrouds the sun... One feels that this inexhaustible fancy is weary at last and worn out with continual exercise, because one is growing into manhood, outgrowing one's old ideals: they are being shattered into fragments, into dust; if there is no other life one must build one up from the fragments. And meanwhile the soul longs and craves for something else! And in vain the dreamer rakes over his old dreams, as though seeking a spark among the embers, to fan them into flame, to warm his chilled heart by the rekindled fire, and to rouse up in it again all that was so sweet, that touched his heart, that set his blood boiling, drew tears from his eyes, and so luxuriously deceived him!