[Question] What are good rationality exercises?

I want to know what are good ra­tio­nal­ity ex­er­cises.

I was just on a call with Liron and PhilH, hang­ing out af­ter the weekly LessWrong week­end event, and we dis­cussed ex­er­cises that could hap­pen on LessWrong.

Here is the list we gen­er­ated:

  • Think­ing Physics

  • Fermi Estimates

  • Pro­ject Euler

  • Cal­ibra­tion Training

  • Ba­sic prob­a­bil­is­tic reasoning

  • Ba­sic have-you-read-the-se­quences knowl­edge test (e.g. “Which of the fol­low­ing is an ex­am­ple of ‘be­lief as at­tire’?”)

Another user on the call (whose name I for­get) sug­gested it could be fun to have a daily Fermi Es­ti­mate on LessWrong, where ev­ery­one sub­mits their num­ber and the model they used to reach the num­ber. I think this would be quite ex­cit­ing.

Please write an­swers with other ex­er­cises that you think are or might be great for ra­tio­nal­ity train­ing, some ex­pla­na­tion of why you think it could be good, and a sug­ges­tion of how it could be in­cor­po­rated into LessWrong. I’ll prob­a­bly add some of the above my­self.