Everybody's got a different circle of competence. The important thing is not how big the circle is. The important thing is staying inside the circle.

What is important is not the quantity of your knowledge but its quality. You can know many things without knowing the most important.

What the wise do in the beginning, fools do in the end.

It's good to learn from your mistakes. It's better to learn from other people's mistakes.

It's much easier to stay out of trouble now than to get out of trouble later.

Knowing the edge of your competency is important. If you think you know more than you do, you will get in trouble.