We must get them to worship “Forces” while denying the existence of “spirits” …..

My Dear Wormwood,

We are really faced with a cruel dilemma.  When the humans disbelieve in our existence we lose all the pleasing results of direct terrorism and we make no magicians.

On the other hand, when they believe in us, we cannot make them materialists and skeptics.

At least, not yet.

I have great hopes that we shall learn in due time how to emotionalize and mythologize their science to such an extent that what is, in effect a belief in us, (although not under that name) will creep in while the human mind remains closed to belief in the Enemy.

The “Life Force,” the worship of sex, and some aspects of Psychoanalysis, may here prove useful.  If once we can produce our perfect work – the Materialist Magician, the man, not using, but veritably worshipping what he vaguely calls “Forces” while denying the existence of “spirits” – then the end of of the war will be in sight….

Once you have made the world an end, and faith a means, you have almost won your man, and it makes very little difference what kind of worldly end he is pursuing.

Provided that meetings, pamphlets, policies, movements, causes and crusades,  matter more to him than prayers,  sacraments and charity, he is ours.

I could show you a pretty cageful down here,

Your affectionate uncle,                                                                                                                         Screwtape

C.S. Lewis in The Screwtape Letters,                                                                                                     Letter VII, pp. 39-43