In Darwin's Dangerous Idea, the philosopher Daniel Dennett makes a useful distinction between two metaphors for two different forms of scientific thinking. There is a form of thinking which uses ‘skyhooks’ and another form of thinking which uses ‘cranes’. A skyhook is an imaginary contrivance in the sky, something which lifts you aloft without any help from below. A crane, by contrast, is something which lifts things up from the ground. In Dennett's words,

For Dennett, Darwinian natural selection is very much a crane mechanism, while Lamarckian theory of inherited acquired characteristics and Teilhard de Chardin's evolutionary utopianism exemplify thinking which uses skyhooks.

I would suggest that, in the field of social and political theory, utopianism bears the characteristics of Dennett's ‘skyhook’ theory, and that this is true of psychological utopianism as well. Jung's and Reich's biology-oriented theories bear more resemblances to the nineteenth-century vitalist Naturphilosophie than with the naturalism of Darwinian biology, while Gross's Communist matriarchy was equally far removed from contingencies of empirical reality. Fromm's Socialist Humanism was somewhat closer to the existing ground, but it still did not exemplify thinking which uses cranes: there was so much Messianism, Marxism and psychoanalytic speculation in his thinking that it is another prime example of a skyhook theory. There is in fact a revelationary element in all psychoutopian thinking, one of the primary functions of which seems to be that it allows us to think that we know something when we know nothing at all.