Egypt forgot how to build the pyramids. Rome forgot how to make concrete that hardens underwater. Both civilizations left behind structures that still stand thousands of years later, and neither one could tell you how they did it. The knowledge wasn’t destroyed. It wasn’t stolen. It simply stopped being used. And the moment it did, it began to vanish. Not slowly. Completely. A skill that isn’t practiced doesn’t pause. It doesn’t wait in storage. It lives in the hands and minds of the people doing the work, and when those people move on without passing it forward, the skill leaves with them. Knowledge is not a possession. It is a maintenance project. It has to be actively held by living minds at work, or it degrades. Not over centuries. Over years. In 1969, the United States put a human being on the moon. Twelve years later, the space shuttle replaced the Apollo architecture. When the shuttle retired, America could not send a single astronaut to orbit on its own hardware. The most powerful nation on Earth had to buy seats on Russian rockets to reach a destination it had conquered decades earlier. Not because the physics changed. Because the people who knew how to do it stopped doing it, and no one replaced them before the knowledge walked out the door. That gap lasted nearly a decade. American astronauts launched on American rockets again only because a private company rebuilt the capability from scratch. We treat advancement as a ratchet. Something that clicks forward and holds. Every generation assumes the next one inherits everything the previous one built and simply adds to it. That is not how it works. Progress is not a ratchet. It is a treadmill. You have to keep running to stay in place. The moment you stop, you don’t pause at the current level. You slide backward. And the slide is silent. It doesn’t announce itself. It doesn’t feel like collapse. It feels like efficiency. Like optimization. Like deciding that maintaining what you built is less important than funding something new. By the time you notice the capability is gone, the people who carried it are already unreachable. Everyone argues about what to build. Nobody argues about the cost of stopping. The cost is not stagnation. It is regression disguised as stability. A civilization that stops building does not freeze in place. It quietly forgets what it knew, and by the time it realizes what it lost, rebuilding costs more than building did the first time. Every generation inherits a world it did not build and assumes the building is finished. That assumption is the first step of the decline. The pyramids still stand. The knowledge that raised them is dust. The aqueducts still carry water. The minds that engineered them are gone. Progress was never a destination you arrive at. It was always a thing you had to keep doing, or lose the ability to do at all. Nobody loses a civilization to a single catastrophe. They lose it the moment they convince themselves that what was already built is enough.

best vibes ever at the women in apps art cafe for @NewYorkAppWeek 💓

For the last ten years I have spent every moment thinking about nothing but air. And how to make better, more personalized air accessible to homes all over the world. And today I can finally present the next huge step in that journey. Introducing Breethr P1, the Personal Climate System. Launching today. And open for pre-orders right now Reserve your P1 for $99: breethr.com Shipping Spring 2027.

妻がパリに来た。 先日の暴動で、あんなに街がメチャメチャになったのに、あっという間に道路が綺麗に戻っていた。 デモ後の掃除もきっと慣れたものなのだろう。 初フランスの妻には綺麗なパリを見せたかったので、ホッとした（笑）。

I was born in France but grew up mostly in Switzerland and London, where I attended the Lycée Français. In 1969, a year after the student uprising, I enrolled at the Sorbonne in Paris. It was an extraordinary time, but a frustrating one for a student who wanted to learn. Too many classes had become forums for political and ideological debates rather than places of academic instruction. After two years, I had enough. I dropped out, bought a one-way ticket to Brazil, and ended up staying for 15 years. I have watched France closely ever since. It remains one of the world’s most beautiful countries, with extraordinary talent, culture, scientific excellence and entrepreneurial creativity. I love France and always will. But over the decades, I have watched a country increasingly constrained by its own institutions. Layers of taxation, regulation, bureaucracy and permitting have made it harder to start businesses, take risks, create jobs and build wealth. Too much energy is devoted to protecting what exists rather than creating what comes next. The result is an economy that struggles to generate the growth and opportunities its people deserve, particularly its younger generations. Instead of looking forward, much of the national debate revolves around how to divide existing wealth rather than how to create more of it. This is not a question of left versus right. Governments of every political persuasion can fall into the same trap. It is about the cumulative effect of policies and institutions that, however well-intentioned, gradually discourage initiative and risk-taking. There is one statistic that I find particularly revealing. In 2025, approximately $320 billion of venture capital was invested in the United States, compared with about $8.4 billion in France. That’s nearly 40 times more in absolute dollars, almost 8 times more per capita, and 4 times more as a percentage of GDP. Venture capital is certainly not the only measure of innovation or economic vitality. But it is an important indicator of a society’s willingness to take risks, back entrepreneurs and invest in its future. America has built an extraordinary ecosystem for turning ideas into companies, companies into industries, and industries into jobs and prosperity. This is one of our greatest competitive advantages. But we should never assume that this advantage is permanent. Excessive regulation, poorly designed taxation, bureaucratic obstacles and political short-termism can gradually undermine the conditions that allow innovation and entrepreneurship to flourish. The damage doesn’t happen overnight. It accumulates over decades, until a country discovers that it has become much better at protecting the past than building the future. I worry about France because I love it. And I worry about America because I don’t want us to make the same mistakes. Prosperity is not something a country inherits forever. Every generation has to create it anew. Let’s not take America’s capacity to innovate, take risks and build for the future for granted.

never belittle someone for their running pace. you have no idea what someone is fighting outside the track. i’ve known people battling suicidal thoughts, families going through divorce, and people dealing with health conditions where death is certain. for some, running is the only thing keeping them mentally and physically alive through their battles. i’ve spent good time with elite and pro runners, and i’ve rarely seen them belittle someone over pace. they never talk about pace. some of the best people i’ve met in running aren’t pros or obsessed with timings we’re all just trying to show up and do our best with the life we’ve been given. be kind. you never know what someone had to overcome just to show up and run

暴動翌日のパリ中心街🇫🇷を歩いた。 ルーブル美術館から凱旋門まで、シャンゼリゼ通りを散歩。 一部の店はガラスが割られ、休業していた。道には焦げたゴミ箱や、催涙ガスの容器らしきものも落ちていた。 ただ、ほとんどの場所はいつも通り。 観光客が歩き、カフェが開き、パリの日常は普通に続いていた。 ニュースで見る「暴動のパリ」と、実際に歩く街の空気は少し違う。

En 1970 aussi la France faisait décoller des fusées et produisait des bonnes voitures. On peut faire de grands exploits. 2500 ans d'histoire nous l'ont prouvé. Mais aujourd'hui la France doit faire un choix. Celui d'oser la liberté. Merci pour les 20k abonnés ! 🫶 🕺

When you are a startup founder, to cope it's either drugs or training. I chose training.

France is arguably the most leftist country on earth & it's still not sufficiently left enough for the protestors there is free healtcare, free education, they work 35-hours a week, 6 week vacation, there is retirement accounts, free immigration, etc the goal is a total destruction of a functioning country, no military, no police, no laws, whatever goes you can not capitulate to the mob, they are finding out & hopefully others wake up

We need France to return to its texhno-capitalist roots More nuclear, more compute, more aerospace, more AI, less bureaucracy Time for 🇫🇷/acc

twitters you do not want to upset, in order: 1. hindutva twitter 2. leftist twitter 3. film twitter (heavy overlap with 2) 4. polysemanticity twitter 5. right wing twitter (most of twitter)