Example is a dangerous lure: where the wasp got through the gnat sticks fast.
The worst time is always the present.
The best laid plot can injure its maker, and often a man's perfidy will rebound on himself.
Even if misfortune is only good for bringing a fool to his senses, it would still be just to deem it good for something.
Rely only on yourself; it is a common proverb.
All the brains in the world are powerless against the sort of stupidity that is in fashion.