[This originally appeared as an article on comp.lang.lisp in response to Kenny Tilton's question about who lured us to lisp.]
How about Bjarne Stroustrup ?
Somewhere[*] he wrote that (I paraphrase) "C++ don't do no double dispatch, if you want that you need to go to a language such as Common Lisp". At this point it struck me that my image of Lisp (cute functional language with more parentheses than practical potential) must be rather flawed. And thus the seed was planted: whenever a reference was made to Lisp I paid attention, and the things I was hearing sounded good.
The final straw came when I was working on a Python/C++ project, and it struck me that I really wanted a dynamically typed language, like Python, that would allow me to program without any type declarations during development, but, when I needed to squeeze the the most out of my CPU, would allow me to provide declarations and to compile to efficient machine code (as opposed to having to re-write the relevant chunk as an extension module in C++).
I wondered how many decades I would have to wait before someone created such a thing (utterly convinced that no such thing could exist today, for, if it would, then we'd ALL be using it, right?), tried to see whether any research was being done in this direction, found Dylan, which turned out to be, well ... Lisp.
I promptly downloaded Clisp, and was stunned to find that so many things I had craved for in a programming language over the years I had dabbled with programming, were there along with plenty more which I never dreamed of.
[*] I thought that it was it The C++ Programming Languge, but I can't seem to find it in there, just now.
Estimated Switch Date 2001 Seek and Ye Shall Find RtL Bjarne Stroustrup