Dear Mr. Stapledon,
I would have thanked you for your book before, but I have been very busy and have only just had time to read it. I don't suppose that I have understood more than a small part - all the same I have understood enough to be greatly interested, and elated too, since sometimes it seems to me that you are grasping ideas that I have tried to express, much more fumblingly, in fiction. But you have gone much further and I can't help envying you - as one does those who reach what one has aimed at.
Many thanks for giving me a copy,