Freakonomics

if morality represents how people would like the world to work, then economics shows how it actually does work.

The conventional wisdom is often wrong.

It is, among other factors, the reality that the pool of potential criminals had dramatically shrunk.

Incentives are the cornerstone of modern life.

Knowing what to measure and how to measure it makes a complicated world much less so.

Dramatic effects often have distant, even subtle, causes.

The fact that economic forces were vastly changing the way a person thought and behaved in a given situation.

The stakes are considered high because instead of simply testing students to measure their progress, schools are increasingly held accountable for the results.

A teacher whose students test poorly can be censured or passed over for a raise or promotion.

Teacher cheating is rarely looked for, hardly ever detected, and just about never punished.