I came to SICP from a totally different path. In 1996 I started programming Scheme and developed my own library for matrix calculus and for symbolic calculus. A

I came to SICP from a totally different path. In 1996 I started programming Scheme and developed my own library for matrix calculus and for symbolic calculus. A few months later I had a copy of SICP in my hands. All the things I did previously on my own now were dealt with in a more systematic and profound way. - Many concepts that I learned from that book became important twenty years later in modern programming languages. Closures, immutability, higher order functions, functions returning functions, etc SICP was a very profound experience. I still have that copy on my book shelf.