These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Socrates Jones Pro Philosopher
Anticlimax Boss: The Final Boss makes many amateur rhetorical mistakes and repeatedly falls into easily-debunked logical fallacies. Half the argument doesn't even require using anything from the idea slate!
Immanuel Kant. His arguments are quite complicated; even the characters complain about how incomprehensible he is. To beat him you need to do something that seems foolish and isn't required anywhere else: use his own philosophy (the first idea he gives you) against him. Even then, figuring out exactly where to do it can be tricky.
Which boss counts as That One Boss for the player may, in fact, reflect their own philosophical beliefs. Philosophers they strongly agree with may be harder to take down; for instance, a deeply religious individual may struggle even against Euthyphro. (It's just as likely that being well-versed in their philosophy may allow one to know all the counterpoints in advance, however.)