List and briefly explain the four principles of personal decision-making

1. People face alternate relationships

Classic alternation: the alternation between cannon and butter.

2. The cost of something is something that is abandoned to get it

Opportunity Cost: something that must be abandoned to get something.

3. Rational people consider marginal volume

Many decisions in life involve small incremental adjustments to existing plans.

4. People respond to incentives

Because people make decisions by comparing costs and benefits, when costs or benefits change, people's behavior also changes. That is to say, people respond to incentives.