Mark, you're a polyglot. I would say for the last 20 years you have been a C++, then Java author more than a Lisp programmer. The first C++ book I ever owned w

Mark, you're a polyglot. I would say for the last 20 years you have been a C++, then Java author more than a Lisp programmer. The first C++ book I ever owned was yours, the one about artificial agents that had a sculpture on the cover, and that must have been 15 years ago. If you're in the business of education, your "toolbox" is essentially whatever people need to learn. You wouldn't hear an English teacher in Korea with 25 years of experience saying she is done teaching English, because teaching Spanish is so much more easier. That doesn't make any sense. At the time you wrote the published Lisp books, it was the height of AI-bubble and people needed to learn Lisp and Prolog. Then you wrote an Smalltalk book (IIRC.) then C++, Java .. all dictated by what the public needed. Btw, you still have the literary and expository prowess to teach today's hot technologies as well. But that doesn't say anything about Lisp, Prolog, Smalltalk, C++, or Java except that you are no longer in the business of teaching them. And I mightly thank you for the Agents book, btw. I didn't know what I was doing and just typed in the code into Borland C++ 4.5. The diskette was missing when I bought it, and I am sure I tried to download the source code from the Addison-Wesley ftp site (it could have been a Prentice Hall book as well) Cheers!