Trouble

The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt. - Bertrand Russell

Wind

When the wind of change blows many people run for cover, others create windmills - Chinese proverb

Knowledge

It is impossible for a man to learn what he thinks he already knows - Epictetus

Suffer

We suffer more often in imagination than in reality - Seneca

Unlearning

Perfecting oneself is as much unlearning as it is learning. Edsger Dijkstra

Decision making

Easy choices, hard life. Hard choices, easy life. - Jerzy Gregorek

The thing

You have to give up the thing you want most in the world, because that's the thing that will destroy you - Bent (movie)