Open Questions

These are questions I don't have satisfying answers to yet:

Macroeconomics: How much evidence do we have that printing money actually helps kickstart the economy? Is there a compelling explanation of why it works?
Macroeconomics: How do stimulus bills work?
- Tbh the whole field of macroeconomics feels like magic to me.

Stonehenge and other henges: Why were they built? How were the stones transported hundreds of miles from Wales to Wiltshire?
- UPDATE: A short post on what we currently know about why and how Stongehenge was built.
How did people from 2000 years ago deal with the fact that their life spans were so short and life was so much riskier? Do you not even realize it because it's the default for the world you live in? Or does it affect your behaviour in some way (e.g. more likely to believe in the afterlife)?

How do we manage to align on notation across so much of the world. E.g. almost everywhere, the way to represent 'the limit of x goes to 0' is exactly the same. How does this consensus process work?

[ANSWERED] What level does natural selection actually work at? Individual, groups, species, something else?
- The selfish gene answered this for me. I wrote about it.

How do distributed locks work? How do they deal with race conditions?
Why is software "eating the world"?
[ANSWERED] How do search engines manage to search across so much data?
- Multiple levels of ranking and indexing. Initially do very lightweight ranking across almost all the documents you have in your index. Index is sharded and you only rank within a single shard. Results from this ranking can be passed on to other services that aggregate results across multiple shards and do heavier ranking. Multi-level ranking can rank an astonishing amount of data.
How do cryptocurrencies work?
- Kind of understand how blockchains work but it still baffles the intuition a bit.
[ANSWERED] How do we end-to-end encrypt conversations without exchanging a key over an unencrypted medium?
- Public key cryptography

How do you run a war?
What type of education do generals get?
How to you handle failure in that kind of a role?
How do you deal with the fact that as a military leader you're taking much less risk than the average soldier? What do soldiers on the frontline think about this?

How do countries successfully do long term planning (> 10 years), when politicians are incentivized by short term outcomes?
- Hypothesis: Mostly they don't.
- But still, it's interesting that sometimes countries are able to do long term planning successfully. E.g. The US looks out for its long term strategic military interests, even though no politician needs to think in that kind of time frame to be elected. Maybe I'm too cynical, and politicians are less self-interested and more patriotic than one would think. Or maybe military beauracrats who have decades-long careers are somehow incentivized to think long term.

How do we decipher ancient texts? E.g. hieroglyphics.
What did the average person do for fun 200, 500, 1000, 2000, and 4000 years ago?

[ANSWERED] How do we assess the price of a stock?
- Discounted cash flow valuations are one approach. Multiples and industry analysis is another. Investopedia explains them well.
Why has the earth's "GDP" has grown by a constant ~2% YoY for the last 2000 years?
- Can't find the source for this anymore, not sure where I read it. Sceptical this is true at the moment, how would you even estimate the GDP of the world 1000 years ago?
How do you get good at investing when your time horizons are 5-10 years or more?
- Delays in feedback make learning difficult. Discipline is required for long periods of time. How does one get good at this?

How to execute on massive 10-year projects of a very wide scope.
- My guess at the moment is that the answer is quite simple - you can't really plan it all out, probably not even at a very high level. You come up with a plausible high level strategy, then just jump in and work it out along the way.
What do CEOs and other senior executives do on a day-to-day basis? What helps them get to their positions?

Some general advice for making sense of magic things

Think about the most plausible explanation, even if you're not sure of the real explanation. Your best guess will probably point you in the right direction > 50% of the time.
Many complex things are learned culturally. Over tens or hundreds of generations, humanity has figured out how to do incredibly complicated things (e.g. farming). To learn farming, instead of learning from first principles, find people who are already good at farming and spend time with them. Learn via osmosis.