This implementation is wholly based on one shared by Evan Dempsey @ SmallSureThing which is in turn based on an earlier implementation. They are pretty simple implementations, so they will not pass any turing tests.
But it makes a more amusing default reply than, "I'm sorry, Dave. I can't do that!"
ref J. Weizenbaum, ELIZA - A Computer Program For the Study of Natural Language Communication Between Man And Machine Communications of the ACM, Vol 9, No 1, January 1966