At the end of Season 1, Matt and I discussed the chapter in Mere Christianity on the subject of sexual morality. C.S. Lewis doesn’t explicitly address the subject of masturbation in that book, but he does in a letter he wrote to the young American named Keith Masson:
“For me the real evil of masturbation would be that it takes an appetite which, in lawful use, leads the individual out of himself to complete (and correct) his own personality in that of another (and finally in children and even grandchildren) and turns it back; sends the man back into the prison of himself, there to keep a harem of imaginary brides. And this harem, once admitted, works against his ever getting out and really uniting with a real woman.
– Personal Letter From Lewis to Keith Masson (1956)
For the harem is always accessible, always subservient, calls for no sacrifices or adjustments, and can be endowed with erotic and psychological attractions which no woman can rival. Among those shadowy brides he is always adored, always the perfect lover; no demand is made on his unselfishness, no mortification ever imposed on his vanity.
The Collected Letters of C.S. Lewis, Volume 3
Here’s Matt Fradd talking about this quotation:
Now that Matt has done this, perhaps I should record an episode on St. Thomas Aquinas’ thoughts on the subject?