My uncle gave me this book as a young child when it first came out in 1977 (now you know approximately how old I am). Unfortunately, I lost my original copy somewhere in the basement of my ancestral home on Long Island. But thanks to Amazon.com, I recently procured a new copy and it simply blew my mind. This may be the finest book ever written on the subject of mathematics. Asimov is better remembered for his fiction, which is excellent as well, but this collection of essays on everything from infinity to Roman numerals to Pi is comprehensive without being boring. It is perhaps even more amazing that none of the material as far as I can tell, is dated in any way. One of my regrets in life was that I was never able to meet Isaac Asimov.