It's awesome for me to have a talk to a man who programs twice as long as my life.

Can you share your views on the future of Lisp? Maybe you have unfulfilled hopes about the future of this language? What was the biggest breakthrough in your 52 years of watching Lisp? (I understand that this is a garbage collector and tail optimization, but as far as I remember, these inventions happened earlier than 52 years ago). What is the biggest limiting factor to your productivity when writing Lisp in Emacs? (for me it's not touch typing oriented enough compared to vim).

How can you personally explain the fact that for all the objective power of any dialect of Lisp, there is still no free software that has utilized the language's capabilities in the same way that Wolfram Alpha does?