Knights, Knaves, and Normals

S1 E4: Now turn to logic puzzles, trying to distinguish between knights who only make true statements, and knaves who only tell falsehoods. Start with simple cases. Then introduce tricky “if–then” statements. Next, what if the knight or knave is insane and thus has false beliefs? This makes things trickier! Finally, add a third category: normal people who are sometimes truthful, sometimes not.