Paradigms of Artificial Intelligence Programming

Now we would like to go a step further and extend the system to handle differenti ation. This is a favorite problem, and one which has historical significance: in the summer of 1958 John McCarthy decided to investigate differentiation as an interest ing symbolic computation problem, which was difficult to express in the primitive programming languages of the day. This investigation led him to see the importance of functional arguments and recursive functions in the field of symbolic computa tion. For example, McCarthy invented what we now call mapcar to express the idea that the derivative of a sum is the sum of the derivative function applied to each argument. Further work led McCarthy to the publication in October 1958 of MIT AI Lab Memo No. 1: