benahorowitz.eth

@bhorowitz

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Joined September 2008

648 Following

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benahorowitz.eth

@bhorowitz

about 1 year ago

Rest in Peace to my father @horowitz39 . We love you Dad. David Joel Horowitz was born January 10, 1939 to Phil and Blanche Horowitz in Queens, New York. David was raised in Queens along with his sister Ruth. Phil and Blanche were high school teachers and members of the American Communist Party. Their lives included secret meetings, secret identities and a secret revolutionary plan. As such, they steeped David in Marxist philosophy and world affairs. We sometimes joked that he was the “Tiger Woods of Communism” as he was raised to be the Party’s next great player. He thought that was funny, because like Tiger he never had a choice in the matter. The impact of his upbringing was profound, but David's life would prove to be shaped by his own self-described irrational desire to “save the world.” While this impulse began as a highly abstract concept, David would spend a lifetime refining it, sharpening it, completely revising it and ultimately making it his life’s mission. David attended Bryant High School in Queens, NY. He received a Bachelor of Arts from Columbia University in 1959 majoring in English. He then earned a master's degree in English literature from University of California, Berkeley. In 1959, he instantly fell in love with and married Elissa Krauthamer. They would have four children: Jonathan Daniel, Sarah Rose, Benjamin Abraham, and Anne Deborah. In 1962, at 23 years old, David wrote and published his first book, Student, which detailed the political activities of students on the UC Berkeley campus. While at Berkeley, David became frustrated with his Shakespeare professor, so he wrote his own lecture series which he delivered and was widely attended by students all across the campus. He eventually published the series in his second book: Shakespeare: an Existential View. This superhuman confidence and ability to back it up would become thematic throughout David’s life. Later David and Elissa moved to London, England where David studied under Ralph Miliband and became close friends with Isaac Deutscher. Later David would write Deutscher’s biography. Also while in London, in 1965 David wrote The Free World Colossus: A Critique of American Foreign Policy in the Cold War, which became the book that made him a force on the new left. In 1968, David and Elissa moved the family back to the United States and purchased a home in Berkeley, California where they would raise their four children. In his continued mission to save the world, in 1968 David became co-editor of the new left magazine Ramparts. While at Ramparts, David developed a close friendship with Huey P. Newton, founder of the Black Panther Party. As part of their work together, David helped raise money for, and assisted the Panthers with, the running of a school for poor children in Oakland. He later recommended that Newton hire his friend Betty Van Patter as bookkeeper; she was then working for Ramparts. In December 1974, Van Patter's body was found floating in San Francisco Harbor; she had been murdered by the Panthers for knowing too much. The murder forced David to confront a truth that he had long suspected. It made clear to him that the pursuit of a marxist utopia was a false and unachievable goal. Diabolically, the goal created a religion. The religion then cloaked the movement’s leaders with an invincible moral standing enabling them to commit atrocities with impunity for their own gain. He was horrified that he had been part of it and it caused him to rethink his entire life. The decision was not easy. His family, friends, and career were all deeply tied to “the movement.” If he were to make this change, he would essentially need to start from scratch. So, he stayed away from politics for a while and changed to a neutral career. He became a biographer and journalist. It was a hugely risky move to change careers at 34 years old with a family of 6 in tow. In a testament to David’s supreme confidence, indomitable will and massive talent, he was an instant success. His first biography The Rockefeller’s An American Dynasty – written with his best friend and long time colleague Peter Collier – was a blockbuster bestseller. Their next biography The Kennedy’s An American Drama was an even bigger success becoming a number 1 New York Times bestseller. All the while, David kept an eye on and a hand in politics. While he needed a break to sort out his life, nothing in life would deter him from his mission. In 1981, San Francisco Chronicle writer Randy Schiltz tipped David and Peter to a potential epidemic known as AIDS, which was rapidly spreading through the bath houses in San Francisco. Schiltz was concerned that the leaders in the Gay Community were intimidating the medical establishment into covering up the way it was transmitted and therefore keeping the bath houses open, which would cause it to spread out of control . Randy was too terrified to write about it himself as he did not want to be attacked by the community. David, never one to fear anything, took on the story. In 1981, he and Peter published Whitewash: Gay Leaders in California Have Obscured Vital Information About How the AIDS Disease Spreads. The aggressive reaction to the story (references to the article still call David a “homophobe”) reinforced David’s suspicions. If leaders on the left were willing to sacrifice millions of gay lives to preserve their power and orthodoxy, what wouldn’t they do? The article, the experience, and the ocean of death that followed were the final straw in David’s conversion from his Marxist roots to a leading thinker on the right. He formalized his position on March 17, 1985 when he and Peter published Lefties for Reagan in The Washington Post. David departed the left for good. The change would cost him nearly everything – all of his friends, coverage in the New York Times Book Review (essential for authors at the time), and countless lost earnings. He would have to start all over. But if the world needed saving from his former comrades on the left, that’s exactly what he would do. Later he would note that the right never excommunicated apostates the way he had been abandoned by the left. He often complained that he had “the rescue gene.” For David, this meant nothing animated him more than someone in need of help. He would instantly leap into action, making every phone call, raising every dollar, and doing anything in his power to save that person. The realization that he had been party to the destructive force activated his rescue gene and infused him with an energy that would produce dozens of books, countless public appearances, and nearly nonstop work for the next 4 decades. In 1996, he captured this saga in his autobiography Radical Son: A Generational Odyssey where he retraced his life’s and political journey. 1998 proved to be a seminal year for David when he met his angel April Mullivain whom he would marry and who, along with her son John Jay, would watch over him until his passing. In 1998, he also founded The Horowitz Freedom Center, where he recruited an inspired group of new young intellectuals to join his cause. The name “Freedom Center” meant much more than most ever understood. While David became known for his change in views, in a sense he never changed at all. His personal style represented the place and community from which he came. Even when he wore a suit, he looked like a radical forced into it due to a court date or a wedding. More importantly, his mission to save the world centered around freedom. When David went to rescue people, it was always from oppression imposed by some person or group. Early on, he had been trained to think the rich capitalists were the oppressors. His political change came from the realization that his side was doing the oppressing. Protected by the guise of being “for the people”, the Panthers took Betty’s life. The progressives left millions to die of AIDS, so they could preserve their leadership positions. His former friends on the left brutally excommunicated him from all their social relationships to reign power over him. It became clear that to fight for freedom, he had to be on the right and so the Freedom Center was born. From the Freedom Center, he published thousands of high impact articles and books. He understood the systematic implications of seemingly benign cultural changes and used that knowledge to predict much of the future. Notably, he precisely forecast the intense campus antisemitism of 2024 in his book The Professors: The 101 Most Dangerous Academics in America published in 2006. In 2007, David was crushed by the passing of his beloved daughter Sarah Rose who, more than any of his other children, inherited his indomitable spirit and passion for politics. She had finally succumbed to long-time chronic degeneration from her genetic condition Turner’s Syndrome. He captured the experience in his most intimate and perhaps his best book A Cracking of the Heart in 2009. By the twenty teens, David had long been frustrated by what he referred to as the “soft, gentlemanly” tactics of the Republican Party. He lamented that the Republicans were bringing a nerf gun to a nuclear war. He intimately knew the left’s tactics and desperately wanted his party to match them. His wish was granted when a new kind of candidate, Donald J. Trump, won the Republican nomination. David responded instantly with the best articulation of the Trump strategy in Big Agenda: President Trump's Plan to Save America. Later, in 2024, his son Benjamin would meet President Trump and mention David. President Trump’s face immediately lit up and he insisted that Benjamin get David on the phone immediately. Hospitalized and weak, David was still delighted to speak with the President and know that his message was heard and heeded. In 2024, David published America Betrayed: How a Christian Monk Created America & Why the Left Is Determined to Destroy Her. In it, he carefully explained how the Catholic Church – through the indulgences – had removed the freedom inherent in being accountable to God and replaced them with the oppression of being accountable to the church. He then explained how that same idea had come back into vogue in the U.S. Right up until the final moments, David fought for freedom. In the end, David helped countless people and expended every fiber of his being pushing society towards freedom. He may not have saved the world, but he most certainly made it a better place – especially for us. He was our super hero and we will love him forever.

bhorowitz's tweet photo. Rest in Peace to my father @horowitz39 . We love you Dad.

David Joel Horowitz was born January 10, 1939 to Phil and Blanche Horowitz in Queens, New York. David was raised in Queens along with his sister Ruth. Phil and Blanche were high school teachers and members of the American Communist Party. Their lives included secret meetings, secret identities and a secret revolutionary plan. As such, they steeped David in Marxist philosophy and world affairs. We sometimes joked that he was the “Tiger Woods of Communism” as he was raised to be the Party’s next great player. He thought that was funny, because like Tiger he never had a choice in the matter. The impact of his upbringing was profound, but David's life would prove to be shaped by his own self-described irrational desire to “save the world.” While this impulse began as a highly abstract concept, David would spend a lifetime refining it, sharpening it, completely revising it and ultimately making it his life’s mission.

David attended Bryant High School in Queens, NY. He received a Bachelor of Arts from Columbia University in 1959 majoring in English. He then earned a master's degree in English literature from University of California, Berkeley.

In 1959, he instantly fell in love with and married Elissa Krauthamer. They would have four children: Jonathan Daniel, Sarah Rose, Benjamin Abraham, and Anne Deborah. In 1962, at 23 years old, David wrote and published his first book, Student, which detailed the political activities of students on the UC Berkeley campus. While at Berkeley, David became frustrated with his Shakespeare professor, so he wrote his own lecture series which he delivered and was widely attended by students all across the campus. He eventually published the series in his second book: Shakespeare: an Existential View. This superhuman confidence and ability to back it up would become thematic throughout David’s life.

Later David and Elissa moved to London, England where David studied under Ralph Miliband and became close friends with Isaac Deutscher. Later David would write Deutscher’s biography. Also while in London, in 1965 David wrote The Free World Colossus: A Critique of American Foreign Policy in the Cold War, which became the book that made him a force on the new left.

In 1968, David and Elissa moved the family back to the United States and purchased a home in Berkeley, California where they would raise their four children.

In his continued mission to save the world, in 1968 David became co-editor of the new left magazine Ramparts. While at Ramparts, David developed a close friendship with Huey P. Newton, founder of the Black Panther Party. As part of their work together, David helped raise money for, and assisted the Panthers with, the running of a school for poor children in Oakland. He later recommended that Newton hire his friend Betty Van Patter as bookkeeper; she was then working for Ramparts. In December 1974, Van Patter's body was found floating in San Francisco Harbor; she had been murdered by the Panthers for knowing too much.

The murder forced David to confront a truth that he had long suspected. It made clear to him that the pursuit of a marxist utopia was a false and unachievable goal. Diabolically, the goal created a religion. The religion then cloaked the movement’s leaders with an invincible moral standing enabling them to commit atrocities with impunity for their own gain. He was horrified that he had been part of it and it caused him to rethink his entire life.

The decision was not easy. His family, friends, and career were all deeply tied to “the movement.” If he were to make this change, he would essentially need to start from scratch. So, he stayed away from politics for a while and changed to a neutral career. He became a biographer and journalist. It was a hugely risky move to change careers at 34 years old with a family of 6 in tow.

In a testament to David’s supreme confidence, indomitable will and massive talent, he was an instant success. His first biography The Rockefeller’s An American Dynasty – written with his best friend and long time colleague Peter Collier – was a blockbuster bestseller. Their next biography The Kennedy’s An American Drama was an even bigger success becoming a number 1 New York Times bestseller.

All the while, David kept an eye on and a hand in politics. While he needed a break to sort out his life, nothing in life would deter him from his mission. In 1981, San Francisco Chronicle writer Randy Schiltz tipped David and Peter to a potential epidemic known as AIDS, which was rapidly spreading through the bath houses in San Francisco. Schiltz was concerned that the leaders in the Gay Community were intimidating the medical establishment into covering up the way it was transmitted and therefore keeping the bath houses open, which would cause it to spread out of control . Randy was too terrified to write about it himself as he did not want to be attacked by the community. David, never one to fear anything, took on the story. In 1981, he and Peter published Whitewash: Gay Leaders in California Have Obscured Vital Information About How the AIDS Disease Spreads.

The aggressive reaction to the story (references to the article still call David a “homophobe”) reinforced David’s suspicions. If leaders on the left were willing to sacrifice millions of gay lives to preserve their power and orthodoxy, what wouldn’t they do? The article, the experience, and the ocean of death that followed were the final straw in David’s conversion from his Marxist roots to a leading thinker on the right. He formalized his position on March 17, 1985 when he and Peter published Lefties for Reagan in The Washington Post. David departed the left for good.

The change would cost him nearly everything – all of his friends, coverage in the New York Times Book Review (essential for authors at the time), and countless lost earnings. He would have to start all over. But if the world needed saving from his former comrades on the left, that’s exactly what he would do. Later he would note that the right never excommunicated apostates the way he had been abandoned by the left.

He often complained that he had “the rescue gene.” For David, this meant nothing animated him more than someone in need of help. He would instantly leap into action, making every phone call, raising every dollar, and doing anything in his power to save that person. The realization that he had been party to the destructive force activated his rescue gene and infused him with an energy that would produce dozens of books, countless public appearances, and nearly nonstop work for the next 4 decades.

In 1996, he captured this saga in his autobiography Radical Son: A Generational Odyssey where he retraced his life’s and political journey.

1998 proved to be a seminal year for David when he met his angel April Mullivain whom he would marry and who, along with her son John Jay, would watch over him until his passing.

In 1998, he also founded The Horowitz Freedom Center, where he recruited an inspired group of new young intellectuals to join his cause. The name “Freedom Center” meant much more than most ever understood. While David became known for his change in views, in a sense he never changed at all. His personal style represented the place and community from which he came. Even when he wore a suit, he looked like a radical forced into it due to a court date or a wedding. More importantly, his mission to save the world centered around freedom. When David went to rescue people, it was always from oppression imposed by some person or group. Early on, he had been trained to think the rich capitalists were the oppressors. His political change came from the realization that his side was doing the oppressing. Protected by the guise of being “for the people”, the Panthers took Betty’s life. The progressives left millions to die of AIDS, so they could preserve their leadership positions. His former friends on the left brutally excommunicated him from all their social relationships to reign power over him. It became clear that to fight for freedom, he had to be on the right and so the Freedom Center was born.

From the Freedom Center, he published thousands of high impact articles and books. He understood the systematic implications of seemingly benign cultural changes and used that knowledge to predict much of the future. Notably, he precisely forecast the intense campus antisemitism of 2024 in his book The Professors: The 101 Most Dangerous Academics in America published in 2006.

In 2007, David was crushed by the passing of his beloved daughter Sarah Rose who, more than any of his other children, inherited his indomitable spirit and passion for politics. She had finally succumbed to long-time chronic degeneration from her genetic condition Turner’s Syndrome. He captured the experience in his most intimate and perhaps his best book A Cracking of the Heart in 2009.

By the twenty teens, David had long been frustrated by what he referred to as the “soft, gentlemanly” tactics of the Republican Party. He lamented that the Republicans were bringing a nerf gun to a nuclear war. He intimately knew the left’s tactics and desperately wanted his party to match them. His wish was granted when a new kind of candidate, Donald J. Trump, won the Republican nomination. David responded instantly with the best articulation of the Trump strategy in Big Agenda: President Trump's Plan to Save America. Later, in 2024, his son Benjamin would meet President Trump and mention David. President Trump’s face immediately lit up and he insisted that Benjamin get David on the phone immediately. Hospitalized and weak, David was still delighted to speak with the President and know that his message was heard and heeded.

In 2024, David published America Betrayed: How a Christian Monk Created America & Why the Left Is Determined to Destroy Her. In it, he carefully explained how the Catholic Church – through the indulgences – had removed the freedom inherent in being accountable to God and replaced them with the oppression of being accountable to the church. He then explained how that same idea had come back into vogue in the U.S. Right up until the final moments, David fought for freedom.

In the end, David helped countless people and expended every fiber of his being pushing society towards freedom. He may not have saved the world, but he most certainly made it a better place – especially for us. He was our super hero and we will love him forever.

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benahorowitz.eth

@bhorowitz

5 days ago

I am very excited to be working with Benham and team on this important mission!

Behnam Neyshabur

@bneyshabur

5 days ago

Today, I’m excited to formally announce @mirendil with my amazing co-founders Harsh Mehta, Shayan Salehian, and Tara Rezaei! We’re fortunate to work with @a16z and @kleinerperkins, who led our seed round of $200M, followed by a major investment from NVIDIA, among others. Mirendil exists to accelerate science and technology, and through them, to help solve humanity's most pressing problems. Self-accelerating AI R&D is the most direct path to delivering on AI's broader promise, which is why we believe the most important application of AI is AI itself. Get this loop right, and it compounds. It fundamentally changes the rate of progress itself across all domains. We believe this capability should be democratized. It should be used to power all scientific efforts trying to innovate at the frontier. There are far more important problems—and broader ones—than any single lab can take on, so more groups should be able to pursue them. This pulls concentration of power away from a few labs: businesses and science labs can own their AI and infrastructure, keep their margins, and control their own destiny instead of ceding it all to a single AI lab. We’re a small team with a singular focus. Our founding team consists of 20 researchers and engineers from frontier institutions including Anthropic, xAI, Google DeepMind, and OpenAI, united by a passion for science and a drive to build the technologies that move it faster. If you want to build the system that builds systems, join us! @HarshMeh1a, @shayan_, @tararezaeikh

bneyshabur's tweet photo. Today, I’m excited to formally announce @mirendil with my amazing co-founders Harsh Mehta, Shayan Salehian, and Tara Rezaei!

We’re fortunate to work with @a16z and @kleinerperkins, who led our seed round of $200M, followed by a major investment from NVIDIA, among others.

Mirendil exists to accelerate science and technology, and through them, to help solve humanity's most pressing problems.

Self-accelerating AI R&D is the most direct path to delivering on AI's broader promise, which is why we believe the most important application of AI is AI itself. Get this loop right, and it compounds. It fundamentally changes the rate of progress itself across all domains.

We believe this capability should be democratized. It should be used to power all scientific efforts trying to innovate at the frontier. There are far more important problems—and broader ones—than any single lab can take on, so more groups should be able to pursue them.

This pulls concentration of power away from a few labs: businesses and science labs can own their AI and infrastructure, keep their margins, and control their own destiny instead of ceding it all to a single AI lab.

We’re a small team with a singular focus. Our founding team consists of 20 researchers and engineers from frontier institutions including Anthropic, xAI, Google DeepMind, and OpenAI, united by a passion for science and a drive to build the technologies that move it faster. If you want to build the system that builds systems, join us!

@HarshMeh1a, @shayan_, @tararezaeikh

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bhorowitz retweeted

TBPN

@tbpn

12 days ago

BREAKING: The great country of Poland has made an $11M investment in ElevenLabs

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benahorowitz.eth

@bhorowitz

13 days ago

Thank you @garcegarce for creating the brand, building the firm and being a great friend to me. We will miss you!!!

Grace Ellis

@garcegarce

13 days ago

Folks, I am closing the books on—gasp—15 years at Andreessen Horowitz. I am still in awe of what we’ve built and do not take for granted these past 15 years, which have felt like 15 minutes in some respects. When the inimitable @wennmachers invited me onboard (I think I was employee number 20-something and thought we were already a sizable firm!), it was to build the brand of a16z and to raise the profile of one @bhorowitz. (Fun fact: One of my first announcements was how the firm had raised a combined $2.7B in our first three years, and one of my last was the $15B we’d closed in January, with now over $100B under management across multiple funds.) While Ben has been a key throughline in my journey, along the way I also had the tremendous privilege and responsibility of leading marketing—first, for our enterprise investing team and portfolio, and later, for our growth fund and portfolio. Both of my boys, now 11 and 7, also came into the world during this time, so a16z is interwoven into the fabric of our lives. I remain beyond proud of the work that we, the marketing team, did over the years, so much of it unsung and behind the scenes. Maybe this time around, I should write the book and Ben, as he once jokingly told me, would do the marketing for it. To know that the brand of a16z is now part of my legacy is remarkable. What makes a place is the people and I take with me some of my deepest friendships. You know who you are and I cannot imagine these past many years without you. ❤️ And to Margit, who made this journey possible, so much love and respect for you. 🙏 As for what’s ahead, I’m fully embracing what I believe to be the true ethos of the firm, which is to expect the unexpected. After a tenure like mine, I really have to close this door before I can even think about opening another, so the only plan I have is to take a well-earned break this summer with my family. 🙌 In the words of my own TeamG, more TK!

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Who to follow

Marc Andreessen 🇺🇸

@pmarca

You’re not talking to someone who woke up a loser. That loser attitude, that loser premise makes no sense to me.

Vinod Khosla

@vkhosla

entrepreneurship zealot, grounded technology possibilist, believer in the power of ideas, passionate about sustainability & impact

Reid Hoffman

@reidhoffman

Co-Founder, LinkedIn. Investor. MSFT Board Member. Building an LLM to discover cures for cancer: @manas_co. Most importantly: Proud American.

bhorowitz retweeted

OpenRouter

@OpenRouter

16 days ago

Introducing the Fusion API, the smartest compound model in the market. Fusion achieves Fable-level intelligence at half the price. How it works 👇

OpenRouter's tweet photo. Introducing the Fusion API, the smartest compound model in the market.

Fusion achieves Fable-level intelligence at half the price.

How it works 👇 https://t.co/OTUQAdTQjU

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benahorowitz.eth

@bhorowitz

17 days ago

It was wonderful to spend time with President Sheinbaum today. She is a fantastic leader and I look forward to working with her on many things.

Claudia Sheinbaum Pardo

@Claudiashein

17 days ago

En Palacio Nacional, recibimos a Ben Horowitz, cofundador y socio general de la firma financiera Andreessen Horowitz. Coincidimos en que México es ejemplo de confianza y certeza económica.

Claudiashein's tweet photo. En Palacio Nacional, recibimos a Ben Horowitz, cofundador y socio general de la firma financiera Andreessen Horowitz. Coincidimos en que México es ejemplo de confianza y certeza económica. https://t.co/CAoZq76ctk

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benahorowitz.eth

@bhorowitz

18 days ago

I am very excited to be working with Yuval for real and not just through a book :-).

Yuval Rooz

@YuvalRooz

18 days ago

Almost 12 years ago, I left @DRWTrading with @wesarn_real to start @digitalasset. @ShaulKfir joined us shortly after. The name felt right. The idea was simple but audacious: build a global settlement system that is asset agnostic. One that doesn’t eliminate banks, exchanges, and intermediaries, but tears down the barriers keeping people from accessing assets and settling at a fraction of today’s cost. A new financial world, built for the end consumer. We knew institutional adoption was the path. We just didn’t know how long it would take. We failed. We made bad decisions. There are things we would have done differently. But we never let go of our North Star, even when people around us were convinced we had no idea what we were doing. That focus, conviction, and most of all, patience, led us to launching @CantonNetwork. And the results speak for themselves. Today is a new chapter in that story. I’m proud to announce that @a16zcrypto is leading our latest round, joined by some of the giants of the global financial system, including @ABNAMRO, ADIA, @apolloglobal, @BNPParibasCIB, @Broadridge, @citsecurities, @CMEVentures, @cbventures, Green Wolf Asset Management, @Hanwha_Official, @HSBC, @icapitalnetwork, @LCVentures, @OptiverGlobal, @polychain, @R136Ventures, @SPGlobal, @sbigroup, @smash_capital, @SoFi, @Tradeweb, and @WilliamBlair, and others we’ll be naming shortly. Twelve years ago, I could not have imagined building alongside partners of this caliber. $CC today processes the highest fees of any institutional blockchain network. And we’re just getting started. What’s coming later this year is just as exciting. None of this happens without the builders, the ones who show up to weekly tokenomics meetings, dial into operations subcommittees, spend nights and weekends building apps on Canton, and show up on @X to cheer this ecosystem forward. You are not just supporters. You are partners. I’m honored to be on this journey with you. On a personal note: @a16z hits differently for me. Ben’s book The Hard Thing About Hard Things was one I kept coming back to during the hard stretches. Having his firm lead this round is meaningful in a way that’s hard to put into words. So I’ll let him do it: “The hard thing isn’t setting a big, audacious goal. The hard thing is spending sleepless nights trying to achieve it. The hard thing isn’t dreaming big. The hard thing is waking up in the middle of the night in a cold sweat when the dream turns into a nightmare. Motivating yourself by watching YouTube shorts or Instagram reels isn’t the hard thing. The hard thing is working every day and being consistent even if you feel like shit. The hard thing isn’t boasting you could achieve anything. The hard thing is working like hell to achieve something. The hard thing isn’t believing in yourself. The hard thing is getting things done when nobody believes in you, even when you doubt yourself. The hard thing isn’t telling yourself that you must achieve the impossible. The hard thing is toiling hard every day for years despite knowing that success is too uncertain.” https://t.co/heqdne7Thh

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benahorowitz.eth

@bhorowitz

23 days ago

Thank you for your service @sriramk !

Sriram Krishnan

@sriramk

23 days ago

🇺🇸🚀 SOME NEWS: I'll be leaving my role at the White House at the end of this month. After a break I’ll be working on helping tackle some of the large challenges facing America on AI (more on that later). It is hard to express how big a privilege it has been to serve the American people and how grateful I am to have had the opportunity to do so. First and foremost, it has been an honor to serve under President @realDonaldTrump . Without his leadership, we would not be leading in the AI race. Second, I owe a lot to the person I’ve worked mostly closely with over the last 18 months - @DavidSacks . His continuing advocacy for America winning on AI has been and continues to be crucial. Some key public accomplishments from last year I’m proud of 1. Architecting and publishing the American AI Action Plan - charting the course for America to win on AI and helping execute on that for the last year. 2. The AI acceleration partnerships to help American AI stack win globally. 3. The National AI Policy Framework for Artificial Intelligence executive order (forming the basis for working with the Hill this year) 4. Advocating for the American AI stack with our allies globally (the AI summits in France and India, state visits to the UK, the Middle East and more) So what’s next? The past 18 months have given me a front row seat to this critical moment on AI facing America and our allies. Whether it is energy, data centers or a clear path for Americans to experience the benefits of AI, there are many tough issues we all need to navigate together. I plan on building institutions that help tackle some of those challenges for America and its allies. I want to thank many others who have helped along the way in the administration : Kevin Hassett, @mkratsios47 , CoS @SusieWiles47 , VP @JDVance , @StevenCheung47 , Sec Bessent, Sec Lutnick, Sec Rubio and @jacobhelberg , @USWREMichael , Will Scharf, Taylor Budowich, @JamesBlairUSA , @elonmusk and many, many others. You know who you are and I know I’ll continue to see you a lot more. Most of all, I want to thank @aarthir on supporting everything and being part of this unexpected but amazing journey from last January. None of this would be possible without her. This journey has been the privilege of a lifetime and shown me how special this country is and how it needs all of us to contribute in anyway we can - and I plan on continuing to do just that. 🇺🇸

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benahorowitz.eth

@bhorowitz

25 days ago

Anne is absolutely amazing. I always wanted to work with her and now I am!

Anne Neuberger

@AnneNeuberger

25 days ago

Today, I’m excited to join Andreessen Horowitz as a General Partner and Head of Global Affairs. This is my next chapter in the mission of securing America at home and ensuring technological innovations are adopted to keep us safe, working together with our allies to build a more secure and prosperous future. Today, as the U.S. and China compete on the global stage, the spread of technology is tinged with geopolitics and more fragmented. Security now requires a focus on digital sovereignty, supply chain resiliency, and the trustworthiness of the infrastructure underpinning our economies and our national security. My full announcement: https://t.co/GEJA7QbkNS

AnneNeuberger's tweet photo. Today, I’m excited to join Andreessen Horowitz as a General Partner and Head of Global Affairs.

This is my next chapter in the mission of securing America at home and ensuring technological innovations are adopted to keep us safe, working together with our allies to build a more secure and prosperous future.

Today, as the U.S. and China compete on the global stage, the spread of technology is tinged with geopolitics and more fragmented.

Security now requires a focus on digital sovereignty, supply chain resiliency, and the trustworthiness of the infrastructure underpinning our economies and our national security.

My full announcement:

https://t.co/GEJA7QbkNS

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benahorowitz.eth

@bhorowitz

25 days ago

Congrats to @arena on Agent Mode!!

Arena.ai

@arena

25 days ago

Introducing Agent Arena: real-world agentic evals at scale. How do you evaluate agents doing actual work? We measure millions of live sessions where real users accomplish real tasks. On Arena, models now get web search, filesystem, and terminal tools to complete complex workflows: writing code, creating slide deck, researching the web, building apps, and analyzing documents. Every session produces rich signals. Users iterate with the agent turn-by-turn: approving, editing, correcting, praise or expressing frustration. The environment gives feedback too: shell errors, tool failures, recovery attempts, and more. Our leaderboard measures each model's agentic performance using causal inference across five signals: task success, steerability, error recovery, user praise vs. complaint, and tool hallucination. This leaderboard snapshot is built from 300K+ tasks, 2M+ tool calls, and 40M lines of code by agents. Top labs in Agent Arena: - #1 @OpenAI: GPT-5.5 (High) - #2 @AnthropicAI: Claude-Opus-4.7 (Thinking) - #3 @Zai_org: GLM-5.1 - #4 @GoogleDeepMind: Gemini-3.1-Pro - #5 @Kimi_Moonshot: Kimi-K2.6 More analysis in the thread, with the full technical blog below.

arena's tweet photo. Introducing Agent Arena: real-world agentic evals at scale.

How do you evaluate agents doing actual work? We measure millions of live sessions where real users accomplish real tasks.

On Arena, models now get web search, filesystem, and terminal tools to complete complex workflows: writing code, creating slide deck, researching the web, building apps, and analyzing documents.

Every session produces rich signals. Users iterate with the agent turn-by-turn: approving, editing, correcting, praise or expressing frustration. The environment gives feedback too: shell errors, tool failures, recovery attempts, and more.

Our leaderboard measures each model's agentic performance using causal inference across five signals: task success, steerability, error recovery, user praise vs. complaint, and tool hallucination.

This leaderboard snapshot is built from 300K+ tasks, 2M+ tool calls, and 40M lines of code by agents.

Top labs in Agent Arena:
- #1 @OpenAI: GPT-5.5 (High)
- #2 @AnthropicAI: Claude-Opus-4.7 (Thinking)
- #3 @Zai_org: GLM-5.1
- #4 @GoogleDeepMind: Gemini-3.1-Pro
- #5 @Kimi_Moonshot: Kimi-K2.6

More analysis in the thread, with the full technical blog below.

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bhorowitz retweeted

Ideogram @ideogram_ai

26 days ago

Introducing Ideogram 4.0: the best open image model in the world. Think it. Make it. Own it. Download the weights, fine-tune on your own data, and run it on your hardware. Live on every Ideogram plan and the API today.

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bhorowitz retweeted

Raghu Raghuram

@RaghuRaghuram

25 days ago

One of the key pillars of the a16z approach is to provide founders with access, power, and resources typically only available to large companies. Today, doing that in the U.S. alone is no longer sufficient. As part of our newly announced a16z global initiatives, we will be helping our Growth companies succeed in this new, global reality. We’ll take the same playbooks and relationship-based approach that have helped our companies in the US and adapt them to international markets. I’m looking forward to working closely with Anne Neuberger in her new role as GP and Head of Global Affairs; Jen Kha and the Global Partnerships team; and our existing go-to-market and talent team, who have been building this foundation for years. More from me here: https://t.co/lYPWrG1WVt

RaghuRaghuram's tweet photo. One of the key pillars of the a16z approach is to provide founders with access, power, and resources typically only available to large companies.

Today, doing that in the U.S. alone is no longer sufficient. As part of our newly announced a16z global initiatives, we will be helping our Growth companies succeed in this new, global reality.

We’ll take the same playbooks and relationship-based approach that have helped our companies in the US and adapt them to international markets.

I’m looking forward to working closely with Anne Neuberger in her new role as GP and Head of Global Affairs; Jen Kha and the Global Partnerships team; and our existing go-to-market and talent team, who have been building this foundation for years.

More from me here: https://t.co/lYPWrG1WVt

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benahorowitz.eth

@bhorowitz

26 days ago

I have been using @townai and it is awesome!

Jean-Denis Greze 💡

@jgreze

26 days ago

Today, we’re launching @TownAI: the AI assistant that learns you. We’re coming out of beta with a $55M Series A led by @ARampell at @a16z, with participation from @KirstenGreen at @forerunnervc and continued support from @firstround, @altcap, and @conviction. Right now, getting real value from AI means prompting, configuring, building workflows, managing agents. We think that’s backwards. The future of AI is a companion that already knows you and how you work. Town connects across your inbox, calendar, Slack, docs, messages, and workflows to understand what you need, then starts doing the work with you. Drafting. Scheduling. Project tracking. Follow-ups. Context gathering. Multi-step tasks. And it only acts when you say so. All adapting to your voice, priorities, routines, and relationships over time. Your Townie is the AI assistant you actually need.

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benahorowitz.eth

@bhorowitz

about 2 months ago

It was a great honor to meet Prime Minister Takaichi @takaichi_sanae I look forward to doing great things in Japan under her leadership.

高市早苗

@takaichi_sanae

about 2 months ago

本日、ベン・ホロウィッツ・共同創業者兼ゼネラルパートナーをはじめとする、アンドリーセン・ホロウィッツ（a16z）社の皆様にお越しいただき、今年夏に、米国内以外で初となる海外拠点を日本に設けることなどについて、御説明いただきました。 a16z社は、フェイスブック、インスタグラムなど多くのスタートアップを育成、支援した実績を有する世界最大級のベンチャー・キャピタルです。高市内閣では、『日本成長戦略』の重要な柱として「新技術立国」を掲げ、スタートアップ・エコシステムの構築を目指しています。また、「経済力」、「技術力」が、我が国の「外交力」、「防衛力」を決するという認識の下、１７の戦略分野の一つとして防衛産業を位置づけています。そうした中で、米国において、産業分野のイノベーションをリードし、安全保障に貢献するスタートアップを見出し、育成してきたa16z社が、「唯一の海外拠点」を日本に開設し、日本への投資拡大、起業家の育成に乗り出すことは、高市内閣の成長戦略、安全保障戦略を進めていく上で実に心強いことです。日本のスタートアップ・エコシステムのダイナミズムを取り入れながら、経済の自律性、技術の優位性や不可欠性を確立することで、「安全保障と経済成長の好循環」を実現していきます。

takaichi_sanae's tweet photo. 本日、ベン・ホロウィッツ・共同創業者兼ゼネラルパートナーをはじめとする、アンドリーセン・ホロウィッツ（a16z）社の皆様にお越しいただき、今年夏に、米国内以外で初となる海外拠点を日本に設けることなどについて、御説明いただきました。

a16z社は、フェイスブック、インスタグラムなど多くのスタートアップを育成、支援した実績を有する世界最大級のベンチャー・キャピタルです。

高市内閣では、『日本成長戦略』の重要な柱として「新技術立国」を掲げ、スタートアップ・エコシステムの構築を目指しています。
また、「経済力」、「技術力」が、我が国の「外交力」、「防衛力」を決するという認識の下、１７の戦略分野の一つとして防衛産業を位置づけています。

そうした中で、米国において、産業分野のイノベーションをリードし、安全保障に貢献するスタートアップを見出し、育成してきたa16z社が、「唯一の海外拠点」を日本に開設し、日本への投資拡大、起業家の育成に乗り出すことは、高市内閣の成長戦略、安全保障戦略を進めていく上で実に心強いことです。

日本のスタートアップ・エコシステムのダイナミズムを取り入れながら、経済の自律性、技術の優位性や不可欠性を確立することで、「安全保障と経済成長の好循環」を実現していきます。

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bhorowitz retweeted

佐藤啓（さとうけい）｜参議院議員（奈良県選挙区）

@sato_kei_nara

about 2 months ago

Andreessen Horowitz to open Japan office by summer, co-founder tells Takaichi https://t.co/6dPP9yuTYA @NikkeiAsiaより

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bhorowitz retweeted

Raghu Raghuram

@RaghuRaghuram

about 2 months ago

It was an honor to meet with Prime Minister Takaichi. We look forward to deepening a16z’s commitment to Japan.

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benahorowitz.eth

@bhorowitz

about 2 months ago

Let's go Dripstack!

Michael Blau

@blauyourmind

about 2 months ago

Honored to see https://t.co/dGx50cN8wm featured as the demo use case for https://t.co/ORJCeP057N by @coinbase / @base !!! Now agents can access, reason over, and act on the best premium financial writing on the internet, while paying writers for the amazing content they create. Try it now: https://t.co/wrtMzZAXQc

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benahorowitz.eth

@bhorowitz

about 2 months ago

I am very excited to be working with Adam, Fred and team!

Adam Jafer

@mradamjafer

about 2 months ago

Today we're launching Pit, with $16M in funding led by a16z. For 20 years, companies have adapted themselves around rigid software, leading to broken workflows and a quiet loss of productivity. With AI, that model breaks. For the first time, companies can run on systems designed around how they actually work, and give back time to their people. We're already seeing large enterprises replace manual operational work with AI-native systems built by Pit. They move faster, scale better, and free people up to focus on higher leverage work. We built Pit because we experienced this pain first-hand at companies like Voi, Klarna, and Zettle. Today, we're also announcing our $16M round led by @a16z, together with some incredible founders and operators from OpenAI, Anthropic, Google, Revolut, Deel, and many more. This is the strongest team I've ever been part of. And we're just getting started.

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benahorowitz.eth

@bhorowitz

about 2 months ago

I am very excited to be working with James and the Ethos team!

Daniel J. Mankowitz

@DJ_Mankowitz

about 2 months ago

Today Ethos announces our $22.75M Series A led by @a16z, with participation from @generalcatalyst, @xtxmarkets, @MattEvantic, and @_CommonMagic. Ethos turns what you know into recurring income - matching your expertise to expert calls, research, AI training, fractional work, and full-time roles. 35,000 people are joining Ethos every week. People are making $10,000 every month on Ethos. AI shouldn’t replace you. It should make you irreplaceable. Build your profile at https://t.co/2jTaj4zmjg.

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bhorowitz retweeted

The Rollup

@therollupco

about 2 months ago

Guy Wuollet (@guywuolletjr), GP at @a16zcrypto, on why they raised $2.2B for crypto Fund 5: "My cypherpunk friends are less excited about the modern era." "Meanwhile, every investment banker and PE friend from college is calling me asking how to use stablecoins to get promoted." "Crypto has finally found its customer profile. That's what fired us up to raise a new fund."