Where ideas compete freely, the prettiest win.
Operations of thought are like cavalry charges in a battle — they are strictly limited in number, require fresh horses, and must only be made at decisive moments.
The more hands your opinions have passed through, the more likely you are to regard them as your own.
Arguments from authority are rarely made by authorities.
Get-rich-quick schemes do less harm than get-wise-quick ones.
Knowing the answer does not oblige you to raise your hand.
The more unusual the topic, the more conventional the thought it inspires.
If you repress thought sufficiently you need not repress speech.