It may seem odd to count the psychology of C. G. Jung as a challenge to religion. It is more usual to complain that, as Freud doffed the physician’s coat for the professor’s gown, so Jung, still more incongruously, has assumed the clergyman’s surplice—if not the robes of the magician, the prophet, the mystagogue. Yet I think that the friendliness of Jung presents a far more serious and radical challenge to religion as we know it than did ever the hostility of Freud.

For Freud, religion was an obsessional neurosis. For Jung it seems to be rather the absence of religion that is at the root of most present-day neurosis among adults. Already in 1932 he wrote: ‘During the past thirty years, people from all the civilised countries of the earth have consulted me. . . . Among all my patients in the second half of life (that is to say, over thirty-five) there has not been one whose problem in the last resort was not that of finding a religious outlook on life. It is safe to say that every one of them fell ill because he had lost that which the living religions of every age have given to their followers.’

How did it come about, this diametrically opposite evaluation of religion—by two psychologists who once worked together in close harmony and considerable mutual admiration? Their early differences, on the surface at least, had nothing whatever to do with religion or philosophy. Jung was every bit as sceptical of both as was Freud. Theirs were wholly professional differences, concerned with the interpretation of actual psychological facts, and with what was, and was not, therapeutically successful.

The coming rift was already visible in Jung’s Wandltmgen und Symbole der Libido, written in 1911. Jung still accepted, even stressed, Freud’s ideas about the origin, and the illusoriness, of religion. But he recognised that traditional religious beliefs and practices (whatever else they may have been) had in fact functioned as a sort of mass-therapy, or at least as a preventive against the sort of neuroses that afflict modem man.