Michael Hartl
@mhartl
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Forever curious. @TauDay founder. @Caltech , @YCombinator alum. “Hartl understands physics deeply… and like Feynman he is an outstanding pedagogue.” —Kip Thorne
Los Angeles, CA
Joined November 2007
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Pinned Tweet
Deep understanding can look like closed-mindedness to the uninitiated.
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There’s absolutely no way I could pass the coding interview at any of the big tech companies. Even the ones where the interviewer learned to code from one of my tutorials.
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One of my uncles was ostensibly an executive at a major oil company, only he wasn’t: it was actually his cover as an agent for the CIA.
If your model of reality doesn’t include intelligence agents in major industry and media organizations, you’re probably missing something big.
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One of my most valuable experiences was watching
#Bitcoin
tumble from nearly $20K to $3K and being totally fine with it. Adopting a long time horizon helped me achieve a Zen-like calm even as I watched a significant fraction of my portfolio evaporate (temporarily) into thin air.
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This interaction is a great example of tech journalism at its worst:
Journo: What role did you play in “co-founding” <company>?
Founder: I started it, recruited other founders, built the core teams, and hired the first ~100 people.
Journo: Sounds pretty handwavy to me! 🤷♂️🙃
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@hollowguit
@gunsnrosesgirl3
The kid is five years old & has been playing piano for less than three years. Millions his age learn the same instrument & study with passion but hardly any achieve such results. What makes the difference? What would it take to convince you that there is such a thing as talent?
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@lexfridman
Gravity: “True, but I prefer to think of light as propagating at the speed of gravity.”
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@martinmbauer
Reminds me of this quote from V. I. Arnold (which I suspect was a bit tongue-in-cheek):
“Mathematics is a part of physics. Physics is an experimental science, a part of natural science. Mathematics is the part of physics where experiments are cheap.”
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It occurs to me that the medieval European economy basically stopped every winter. We need to work toward a society where people of all economic means are able to take off as much time as medieval peasants. For all our ostensible wealth, our society is fragile and unsustainable.
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I’m aware, of course, of the counterargument that Bitcoin’s energy use is “wasteful”, but this simply begs the question. Everyone agrees that if Bitcoin is useless, its energy use is wasteful. But
#Bitcoin
is exceptionally useful, with benefits that greatly exceed its costs.
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Math Olympiad is hard. Unless they have deep experience in contest math, nearly everyone (including
@pmarca
and Thiel) would get a 0 on a typical Math Olympiad exam. Indeed, I’d guess that many (probably most) people with bachelor’s degrees in math would score 0 or close to it.
Live timed math olympiad competition between pmarca vs thiel. Who would you bet on ?
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Math textbook titles (for, say, number theory) by how advanced they are:
Beginning undergrad: Elementary Number Theory
Advanced undergrad: Elementary Number Theory
Beginning grad: An Introduction to Number Theory
Advanced grad: Basic Number Theory
N.B. These are all real books.
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@anymanfitness
I applaud your sentiment overall but the last sentence makes no sense. Do people not remember Newton, or Michelangelo, or Beethoven? I think the world would probably be a better place if they’d had lots of kids, but clearly they left remarkable legacies despite having none.
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It seems that every generation needs to learn anew that (a) you probably want a relational database on the back-end and (b) that database should be PostgreSQL.
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No one who has studied the sad history of monetary dilution—from the Romans debasing the denarius as the Empire fell, to hyperinflation in revolutionary France or Weimar Germany, to the many inflationary regimes of today—could possibly claim that
#Bitcoin
is “useless”.
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@pettyblackgirI
@schneems
This is basically flawless Krav Maga–style technique: strike to the face, groin kick, knee strike. Over & out. 💯
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@Dennis_Porter_
The market cap of gold is around $11.7T. Dividing this into 21M bitcoins gives approximately $557K/BTC. If you believe, as many Bitcoiners do, that equaling the market cap of gold yields a conservative estimate on BTC’s eventual price, $1M/BTC seems plausible and even rather low.
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@realohtweets
I’ve legit googled for Rails syntax that turned up my own tutorial as the first result.
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@TheRealElaschuk
@MNateShyamalan
@Popehat
Had to look this one up. It’s a great story, but apparently the original song included an illustration indicating that they are in fact just five gold rings.
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@captainsafia
@github
I wrote a `git-utils` library that literally supports `git typo` for this exact purpose.
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@GrantSlatton
Reminds me of this anecdote regarding Italian:
@_holyweather
When I lived in Italy, I was having trouble making myself understood for even really basic things I knew I knew how to say, until one day I got so frustrated I started trying it in a ridiculous Mario accent... and it worked.
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There’s no sharp dividing line between “mental” and “physical” health. Mental is physical.
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@KelseyTuoc
I impressed the heck out of my future AP Computer Science and Calculus teacher when he said his kid was having trouble finishing the Legend of Zelda and I showed up the next day with carefully annotated hand-drawn maps of Ganon’s lair. Video games FTW!
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@docentdemagogue
@mattparlmer
It seems we can file this one under “predictable unintended consequence of well-intended law.” (We all know the destination of the road that’s paved with good intentions.)
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“Knocking Go to fourth place, Ruby on Rails surfaced as the most in-demand skill for software engineering roles, creating 1.64x more interview requests for the developers proficient in it.”
That’s not 2013, folks—it’s 2023.
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@robinhanson
I grabbed this story off of Facebook a few years back. It does a great job of reframing what the “truth about Santa Claus” really means.
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Blackouts are coming to California. If only there were an abundant, energy-dense, zero-emissions source of power. Wouldn’t that be great?
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@Austen
Derek Sivers once told me a story about when he was considering living in Iceland. While visiting a restaurant there with an Icelandic friend, he saw that a group of people had left an iPhone at their table. Derek thought they should tell them they’d left it, but his friend said
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I mentioned agents in particular because it’s the more extreme case, but assets and informants (i.e., those who are generally aligned and coordinated with intelligence agencies) are also important.
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As an experienced coder, I’ve developed a refined system for making good Git commits:
<500 lines of code>
$ git commit -am "Implement feature"
<2 lines of code>
$ git commit -am "Fix bug"
$ git commit -am "Fix typo"
$ git commit -am "Fix typo"
$ git commit -am "Fix typo"
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New favorite Community Notes just dropped.
#MerryChristmas
🎅🏻
I captured this photo as Santa and 8 reindeer transited the nearly full moon. These shots require more luck than skill, as there is no telemetry that allows me to reliably track his movements.
Those with telescopes, turn them upwards and try and capture this elusive sight!
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Looking at Bitcoin and concluding that we're in a massive bubble is completely reasonable. It's also wrong. Bitcoin's rise is a monetization event, which has a positive feedback loop where a bubble has a negative one. Traditional financial intuition is thus a poor guide.
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@AdamAlethier
@naval
>Why should covid be any different?
Because this time the regime has learned how to use it as a bludgeon against its perceived enemies.
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The greatest trick sugar ever pulled was convincing the world it isn’t a drug.
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I’m running for president on the platform that America should conquer Europe, remove the GDPR cookie law, and then leave.
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Never cede the moral high ground to these zealots. Monocrop agriculture does far more damage to ecosystems than raising cattle. Indeed, in many cases the presence of hoofed ruminants—which once walked the land in great numbers—contributes to a healthy ecological balance.
Today we announced that Epicurious is cutting out beef. It won’t appear in new Epi recipes, articles, newsletters, or on social. This isn’t a vendetta against cows or people who eat them. It’s a shift about sustainability; not anti-beef but pro-planet.
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(The scare quotes on “co-founding” were a particularly nice touch.)
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@JanWues
@PeterZeihan
Also saying that a currency with a fixed supply is inflationary. His understanding of monetary theory is so bad that it’s indistinguishable from trolling.
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It sounds like I might have to amend this a little: It’s possible I would pass if I got a sensible interviewer like
@the_thagomizer
. But the broader point remains: There’s a good chance I would flunk if the luck of the draw didn’t break my way.
@ericqweinstein
@mhartl
@lsegal
Luck of the draw mostly. There’s also some variation by role. I’m not a software engineer. I’m a DevRel engineer. Still had to code in all my interviews.
In the last two years there have been changes to the interview process too. I expect more in the future.
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@dhh
It’s not uncommon for me to google some bit of Rails syntax and find the answer in the
@RailsTutorial
—one of several reasons why I’m generally comfortable admitting my ignorance quite publicly.
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This dog has just accepted an offer from the mathematics faculty at Princeton University to study knot theory.
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@ByrneHobart
Is this true? The general subject is a hobby interest of mine but I don’t recall ever hearing this.
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@paulg
@cremieuxrecueil
Terry Tao is my go-to contemporary counterexample for the shockingly large number of people who refuse to concede that there’s such a thing as “mathematical talent”. As I noted in the original thread, the whole article is worth reading:
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I ran into Arnold
@Schwarzenegger
yesterday at
@GoldsGym
, where he was gracious enough to join me in a selfie. I grew up watching his films and was also influenced early on (dating back to my
@Caltech
days) by his book “Arnold: The Education of a Bodybuilder”. Great to meet him!
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If only there were some commonly available product that let you easily see the actual size of countries.
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@NickSzabo4
@serumroth
@RajarshiMaitra
@BobMcElrath
@adam3us
“No amount of investigation of yours would succeed in attaining the proof, and yet, once seen, you immediately believe you would have discovered it; by so smooth and so rapid a path he leads you to the conclusion required.”
—Plutarch, on Archimedes
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Phrases to avoid when discussing a difficult topic:
Obviously
Of course
It is clear that
It is easily seen that
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The collaboration between
@Stripe
and
@Shopify
mentioned in this article is a good reminder that you should only use
#Ruby
if you want to be limited to creating a ~$100 billion company. Any valuation higher than that is untested at this time.
We've described Stripe for a few years as a global payments and treasury network; delighted to announce today more progress on the treasury front.
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@messi2119
@paulbohm
What part of “some years ago (when I had no money)” didn’t you understand?
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So many highly effective people are assholes that it's tempting to think their assholery contributes to their success. But I suspect it's selection bias: only highly effective assholes are tolerated. They'd be even more effective if they were tactful, diplomatic, and polite.
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There's a lot of confusion out there about what Bitcoin is and why it matters, but its primary purpose can actually be summarized in a single sentence:
Bitcoin is sound money for the digital age.
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The
#Bitcoin
community is lucky to have an exponent as articulate, concise, and likeable as
@real_vijay
.
“When you get close to global adoption, meaning everyone has some
#Bitcoin
, the purchasing power will stabilize. And that is when it becomes suitable as a medium of exchange.”
@nickgillespie
caught up with
@real_vijay
at
@TheBitcoinConf
in Miami.
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Prediction: Someday "billionaire" will mean "owns at least one billion satoshis".
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@Mangan150
@saifedean
It’s the censorship that most puts the lie to the “we didn’t know” defense. I’m willing to concede the possibility that there may have been genuine uncertainty for a (very short) time, but the proper response to “we don’t know” is never “mercilessly suppress dissent.”
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I see a lot of people mocking this or making snarky replies, but I guarantee
@paulg
meant it only as an interesting observation. There are many insincere shills and dishonest hacks in the world, but PG is not one of them. Indeed, he may be the most honest & sincere person I know.
A friend of mine who is basically never wrong about financial questions converted 80% of his Bitcoin into Ethereum.
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@NimbleMariota
Heh. The second I saw it I thought, "The Internet starts making fun of the missed handshake in 3, 2, 1…"
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See this outstanding thread from
@michael_saylor
for more.
#Bitcoin
Mining serves as the foundation of the monetary network - critical to its growth, stability, longevity, vitality, & integrity. The Proof of Work architecture is a masterpiece of engineering that anchors the system to the real world, providing Seven Layers of Security.
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If it’s any consolation to the biologists, “googling commands we use all the time” describes basically all the programmers I know, including me.
“Biologist should learn to code”
do any of us know how to code tho or are we all just googling commands we use all the time but still can’t remember
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