A.J

Imagine paying $500 and getting a first row seat and you watch this… Literally the Second worst Tennis style 🤦

The greatest discovery of Adler is the realization that the life problems we don’t solve, we don’t solve on purpose because they serve some deeper utility to our psyche. So much so that someone could provide you step by step instructions for how to solve your problem in a way that is far easier than dozens of other things youve done before without complaint, and your immediate reaction will be to invent every possible roadblock for why it will never work. And that if they keep providing you solutions to those roadblocks, you will get increasingly upset. This is the opposite of what you’d do if you wanted it solved. But exactly what you’d do if you didn’t want it solved. The truth is you LIKE having this problem. It is a part of your IDENTITY. And you wouldn’t even know what to do with yourself or who you would be if it wasn’t a problem anymore.

Jane Street made ~$40B in 2025 with 3,500 employees, a ~2x from the year before. At ~65-70% profit margin, that's $8M profit / employee, the highest for a 1000+ ppl company. High-frequency trading continues to be the most efficient money making engine. I want to share an old story about my Jane Street interview in 2014. Jane Street was known for hiring a lot of math, physics and CS olympiad winners from top universities and putting them through many rounds - including, for trading roles, a gauntlet of mental math. It was my 6th interview and my final round and I recall being asked "What is the next day after today in DD/MM/YYYY where all the digits are unique?" They'd toy with you and say "You can use a pencil and paper, if you want" but you knew that was an instant no. Painstakingly and as quickly as I could, I came to an answer. "How confident are you that this is correct on a 0-1 probability scale?" the interviewer said. "0.95", I blurted out, not fully knowing how to answer that. "Are you sure?" After thinking harder for a few more seconds, I realized I could've flipped the digits around to get a closer date. I gave the interviewer my answer. It was correct. "0.95 huh?" he chuckled. That's when I knew I failed. Note: fwiw, other companies that come close in efficiency are - Tether ($90M+ profit/emp) - Hyperliquid ($80M+ profit/emp) and on revenue: - Valve ($50M/emp) - OnlyFans ($37M/emp) - Craigslist ($14M/emp) - Anthropic ($12M/emp, run rate) - OpenAI ($8M/emp, run rate) For comparison, Nvidia is very efficient at scale and is $4.4M/emp.

Americans spent over $109 billion on lottery tickets last year, which is more than they spent on movies, books, concerts and sports tickets - combined.

Your income is strongly predicted by your parents’ income. “Self-made” is rarer than people think.

My opinion, maybe unpopular, is I don’t think the human arm was meant to withstand hitting a tennis ball repeatedly at 100 mph