People have been hunting for a certain quote recently, and I thought perhaps it would be useful to give it with some of its context.
The next great heresy is going to be simply an attack on morality; and especially on sexual morality. And it is coming, not from a few Socialists surviving from the Fabian Society, but from the living exultant energy of the rich resolved to enjoy themselves at last, with neither Popery nor Puritanism nor Socialism to hold them back... The roots of the new heresy, God knows, are as deep as nature itself, whose flower is the lust of the flesh and the lust of the eye and the pride of life. I say that the man who cannot see this cannot see the signs of the times; cannot see even the skysigns in the street that are the new sort of signs in heaven. The madness of tomorrow is not in Moscow but much more in Manhattan - but most of what was in Broadway is already in Piccadilly.
[GKC, G. K.’s Weekly, June 19, 1926; quoted in Maycock, The Man Who Was Orthodox, 123]