From the number of technical articles and reports Paul Graham writes on a regular basis, aside from other teaching work he might be involved in, I guess it's always more prudent to just learn lisp on your own and then try to decypher his spam lisp code with the gained knowledge. Imagine if there were literally hundreds of 'fans' seeking this knowledge from the wise? This could overwhelm anyone, even a guy holding Ph.D. Besides, even if he were to explain the code, he'll do it from the point of view of a Lisp expert and resort to describing aspects of Lisp involved in the code. Therefore, the best option then becomes to simply read an online Lisp reference on your own.
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# Under Construction