Today I turn 40.  To ease the pain, I’ve decided to write a list of important lessons I’ve learned during my first four decades.  In no particular order:

Economics

1. Supply-and-demand solves countless mysteries of the world – everything from rent control to road congestion.

2. Almost anyone can understand supply-and-demand if they calmly listen.  Unfortunately, the inverse is also true.

3. Poverty is terrible, and economic growth, not redistribution, is the cure.

4. The proximate causes of unemployment are labor market regulation and workers’ misguided beliefs about fairness.  But the fundamental cause of unemployment is excessive wages.

5. Free competition is far superior to “perfect” competition.

6. Governments with fiat money have near-absolute power over nominal GDP, but much less over real GDP or employment.

7. Moral hazard and adverse selection are largely the product of – not a rationale for – regulation of insurance.

8. Immigration restrictions are a fruitless crime – and do more harm than all other government regulations combined.

9. Communism was a disaster because of bad incentives, not lack of incentives.

10. The last two centuries of rising population and prosperity should fill us with awe – and the best is yet to come.

Philosophy

1. The greatest philosophical mistake is to demand proof for the obvious.  See Hume.

2. The second greatest philosophical mistake is to try to prove the obvious.  See Descartes.

3. If you can’t explain your position clearly in simple language, you probably don’t understand it yourself.

4. When possible, resolve debates about “what’s obvious” by betting, not talking.

5. Ignoring the facts of dualism and radical free will is anti-empirical and unscientific.

6. Talking about morality if there are no moral facts is like talking about unicorns if there aren’t any unicorns.

7. There are moral facts.

8. Productive moral arguments begin with clear-cut simple cases, not one-sentence moral theories or trolley problems.

9. Violence and theft are presumptively wrong, and calling yourself “the government” does nothing to rebut these presumptions.

10. The best three pages in philosophy remain Epicurus’ “Letter to Menoeceus.”

Politics

1. Voters are irrational.  So is believing otherwise.

2. Government isn’t a solution to externalities problems; it’s the best example of the problem.

3. The main output of government isn’t “public goods,” but private goods that people pretend to want much more than they really do.  See Social Security and Medicare.

4. People rarely make the the most internally consistent argument for government action: paternalism.

5. The realistic path to freer markets isn’t “free-market reform,” but austerity.

6. Democrats and Republicans are about as different as Catholics and Protestants – and 80% of the union of their mutual recriminations is true.

7. Before you study public opinion, you wonder why policy isn’t far better.  After you study public opinion, you wonder why policy isn’t far worse.

8. Big reasons why democracy isn’t worse: Unequal participation, political slack, and status quo bias.

9. Libertarians are the dhimmis of democracy.

10. Despite everything, life in First World democracies is amazingly good by world and historic standards and will keep getting better.  So cheer up.

Life

1. Life is a gift, and the more the better.

2. “Do what you love and you’ll never work a day in your life.”  Yep.

3. Be friendly as a matter of policy.  Turn the other cheek in the face of ad hominem attacks.  It might seem crazy, but it works.

4. Obsessiveness is an powerful solution for physical and social problems.  Unfortunately it’s also a major cause of emotional problems.

5. Once you’re an adult, religious people will leave you alone if you leave them alone.

6. People vary more widely than you think.  Tell yourself it’s nobody’s fault.

7. Selection is the key to social harmony.  Surround yourself with true friends who love you just as you are.  If you don’t see any around, quest for them.

8. Raise your children with kindness and respect.  “I’m your parent, not you’re friend” is a reason to treat your kids better than their peers do, not worse.

9. Your mind ages at a slower rate than you expect when you’re young, your body at a faster rate.

10.  Evolutionary psychology is by far the best universal theory of human motivation.  Ignore it at your own peril.