Love Philosophy! It was my favorite class in college and I think I was the only student who had an interest in the subject - most people fell asleep.I mostly read old 20's to 50's readers and American history textbooks. We actually have a bunch of books we want to give away, but it's probably not something library patrons want to read!
Titles of a few newer-ish ones on my bookshelf though:
Battle at Sea
The Philosophy Book
George Washington's World
The Mad Scientists' Club
To Sanctify the World
I am currently reading The Sacred Depths of Nature by Ursula Goodenough. She is a professor of Biology at the St. Louis Washington University. From the jacket - "Looking at topics such as evolution, emotions, sexuality and death, Goodenough writes with rich, uncluttered detail about the workings of nature in general and of living creatures in particular. Her clarity makes it possible for non scientists to appreciate the origins of life and the universe."
If you don't enjoy biology, you might not like the book. It is a fascinating read and she eloquently intertwines reverence of the Divine. It's a humbling read and will make you look up at the sky and wonder.....