The fist number of L. refer to the standard CtP edition published in 1987. The following number shows correspondence between letters in the new 2010 edition. Note that on this website CtP is available only 1987 edition with minor additions.

[L. 123 | 133] 23 April 1964

Many thanks for your letter of the 21st, just received. It is very good of you indeed, not only to have sent the addresses, but also to have been so thoughtful as to make the suggestion about an occasional loan of 'books with a philosophical background'. As things are, your suggestion is really rather welcome. Although a preoccupation with books should not be our prime concern, I am much handicapped by chronic sickness and find that some reading and a little writing do help out over difficult periods. And, as you will be aware, we are more or less entirely dependent on the kindness of others in such matters as the provision of books.

As I expect you are aware, a copy of my Notes on Dhamma was sent to your library a few months ago (and duly acknowledged). But I quite recognize that it is not everybody's cup of tea—Buddhists, at least in Buddhist countries, have long since given up thinking, and thinkers have not yet begun to learn Pali. For the benefit of the thinkers, any future edition will be provided with English translations, but the problem is not solved so easily of getting the Buddhists to think.