This is the famous eliza chat bot.

https://en.wikipedia.org/wiki/ELIZA

I think it shows exceptionally well what computers can and can't do:

• Skilled developers can easily create programs that will beat the old turing test.

• The program is obviously not smart in any way and it's really easy to "pop the hood and look at the insides" and explain why.

• I think to this day, it shows the limits, opportunities and challenges of processing natural language.

The real mystery about "why it works" is about the setup and setting that Weizenbaum used and in the specific language and purpose of the language he put in as preprogramed responses for eliza to say.

It's a script I found online and modified a bit. Although it works out of the box with python 3, unlike the exact script I found.

I think I will use it as a base to explore chat bots and NLP.