Heraclitus thought everything was in an endless state of change, so we could never 'step into the same river twice'.

Descartes tried to methodically doubt everything, much like children do when they ask an endless stream of 'whys'.

Hume doubted that inductive reasoning was strictly rational, so even if someone had past behavior such as cheating, there was no 'rational' reason to use that to predict future events.

Nietzsche was a loser.

Hegel was long winded.

Nozick's entire philosophical project was justifying extreme wealth disparity as having arisen from 'free' decisions.