Why not say that the meaning and purpose of the sexual powers is pleasure? Certainly sex is pleasurable, but there is nothing distinctive about that. In various ways and degrees, the exercise of every voluntary power is pleasurable. It is pleasurable to eat, pleasurable to breath, even pleasurable to flex the muscles of the leg. The problem is that eating is pleasurable even if I am eating too much, breathing is pleasurable even if I am sniffing glue, flexing the muscles of the leg is pleasurable even if I am kicking the dog. For a criterion of when it is good to enjoy each pleasure, one must look beyond the fact that it is a pleasure. Consider an analogy between sex and eating. The purpose of eating is to take in nutrition, but eating is pleasurable, so suppose that we were to say that the purpose of eating is pleasure, too. Then it would seem that any way of eating that gives pleasure is good, whether it is suitable for nutrition or not. Certain ancient Romans are said to have thought this way. To prolong the pleasure of their feasts, they purged between courses. I hope it is not difficult to recognize that such behavior is disordered. The more general point I am trying to make is that although we find pleasure in exercising our sexual powers, pleasure is not their purpose; it only provides a motive for using these powers, and a dangerous one, too, which may at times conflict with their true purposes and steer us wrong. Besides, to think of pleasure as the purpose of intercourse is to treat our bodies merely as tools for sending agreeable sensations to our minds. They are of inestimably greater dignity than that, for they are part of what we are.
The first objection is that it is rubbish to talk about natural meanings and purposes, because we merely imagine such things. According to the objector's way of thinking, meanings and purposes aren't natural—they aren't really in the things themselves—they are merely in the eye of the beholder. But is this true? Take the lungs, for example. When we say that their purpose is to oxygenate the blood, are we just making that up? Of course not. The purpose of oxygenation isn't in the eye of the beholder; it's in the design of the lungs themselves. There is no reason for us to have lungs apart from it. Suppose a young man is more interested in using his lungs to get high by sniffing glue. What would you think of me if I said, “That's interesting—I guess the purpose of my lungs is to oxygenate my blood, but the purpose of his lungs is to get high?” You'd think me a fool, and rightly so. By sniffing glue, he doesn't change the purpose built into his lungs, he only violates it. We can ascertain the purposes of the other features of our design in the same way. The purpose of the eyes is to see, the purpose of the heart is to pump blood, the purpose of the thumb is to oppose the fingers so as to grasp, the purpose of the capacity for anger is to protect endangered goods, and so on. If we can ascertain the meanings and purposes of all those other powers, there is no reason to think that we cannot ascertain the meanings and purposes of the sexual powers. Natural function and personal meaning are not alien to each other. They are connected. In a rightly ordered way of thinking, they turn out to be different angles of vision on the same thing.The second objection is that it doesn't make any difference even if we can ascertain the meanings or purposes of the sexual powers, because an is does not imply an ought. This dogma too is false. If the purpose of eyes is to see, then eyes that see well are good eyes, and eyes that see poorly are poor ones. Given their purpose, this is what it means for eyes to be good. Moreover, good is to be pursued; the appropriateness of pursuing it is what it means for anything to be good. Therefore, the appropriate thing to do with poor eyes is try to turn them into good ones. If it really were impossible to derive an ought from the is of the human design, then the practice of medicine would make no sense. Neither would the practice of health education. Consider the young glue-sniffer again. How should we advise him? Is the purpose of his lungs irrelevant? Should we say to him, “Sniff all you want, because an is does not imply an ought”? Of course not; we should advise him to kick the habit. We ought to respect the is of our design. Nothing in us should be put into action in a way that flouts its inbuilt meanings and purposes.
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.
However, questions arise. Are there people who aren't naive realists, or special situations in which naive realism disappears? My theory—the self-model theory of subjectivity—predicts that as soon as a conscious representation becomes opaque (that is, as soon as we experience it as a representation), we lose naive realism. Consciousness without naive realism does exist. This happens whenever, with the help of other, second-order representations, we become aware of the construction process—of all the ambiguities and dynamical stages preceding the stable state that emerges at the end. When the window is dirty or cracked, we immediately realize that conscious perception is only an interface, and we become aware of the medium itself. We doubt that our sensory organs are working properly. We doubt the existence of whatever it is we are seeing or feeling, and we realize that the medium itself is fallible. In short, if the book in your hands lost its transparency, you would experience it as a state of your mind rather than as an element of the outside world. You would immediately doubt its independent existence. It would be more like a book-thought than a book-perception. Precisely this happens in various situations—for example, In visual hallucinations during which the patient is aware of hallucinating, or in ordinary optical illusions when we suddenly become aware that we are not in immediate contact with reality. Normally, such experiences make us think something is wrong with our eyes. If you could consciously experience earlier processing stages of the representation of the book In your hands, the image would probably become unstable and ambiguous; it would start to breathe and move slightly. Its surface would become iridescent, shining in different colors at the same time. Immediately you would ask yourself whether this could be a dream, whether there was something wrong with your eyes, whether someone had mixed a potent hallucinogen into your drink. A segment of the wall of the Ego Tunnel would have lost its transparency, and the self-constructed nature of the overall flow of experience would dawn on you. In a nonconceptual and entirely nontheoretical way, you would suddenly gain a deeper understanding of the fact that this world, at this very moment, only appears to you.