EPUB - https://github.com/sarabander/sicp-epub/blob/master/sicp.epu...

PDF - https://github.com/sarabander/sicp-pdf/raw/master/sicp.pdf

https://melpa.org/#/sicp

> Exercise 1.1: Below is a sequence of expressions. What is the result printed by the interpreter in response to each expression? Assume that the sequence is to be evaluated in the order in which it is presented.

There are then 12 simple expressions to evaluate. That is, it took them nearly 40 minutes for each expression.

Exercise 2.46 took them 535 minutes to implement. It wasn't even complex math, they needed to create a 2d-vector data type (their choice on implementation details) with a constructor, accessors, addition, subtraction, and scaling. That should not have taken 9 hours to complete (not by that point in the book at least).

I suppose it is something to do with the fact that it has been, what, almost 40 years since the lectures?

The fact that most of the code would still work is a miracle. That wouldn't work for, say, Java (which didn't exist in 1986). Nor C++. Nor Javascript (also not there back then). Fortran and C might be able to pull it off (but barely).

Remember, we didn't have computers worth the name back then. Shoot, we didn't even have dirt yet, just rocks.