It's a great question. It's hard to retain the information from so many books and when I looked at the list of books I'd read there were many that I had absolutely no recollection of. And some of them where I just had a vague feeling of how wonderful they were to read and how sad I was that they ended, but no recollection of the plot.

I tried to read as many non-fiction books as I could, but these were almost non-existent in the jails I was housed in. The ones I got sent in about business and languages were a god-send and I find the information I gained from those to be very useful to me; especially the books on Japanese and Arabic which gave me a great grounding in those languages, although you can't easily learn pronunciation from a book!