John Schulman

American AI researcher, a co-founder of OpenAIOpenAI, prop. n.: The American company that makes ChatGPT and the GPT models. It began in 2015 as a nonprofit research lab and is now a for-profit company overseen by a nonprofit foundation. and of Thinking Machines LabThinking Machines Lab, prop. n.: Mira Murati's AI company, which she started in San Francisco in 2025 after serving as OpenAI's technology chief. It makes tools for customizing AI models and releases some models openly.. As a doctoral student of Pieter AbbeelPieter Abbeel, prop. n.: A Belgian-American roboticist at Berkeley whose research taught robots to learn from demonstrations and from trial and error, and who co-founded the robotics company Covariant. at the University of California, Berkeley, he introduced trust region policy optimizationtrust region policy optimization, n.: A method for improving an AI's strategy in careful steps, never changing it too much at once, so that a single bad update cannot wreck what it has already learned. (2015) and generalized advantage estimationgeneralized advantage estimation, n.: A recipe for judging how much better each action was than expected by blending short-term and long-term evidence, trading a little accuracy for much steadier learning. (2015); at OpenAI he created proximal policy optimizationproximal policy optimization, n.: A widely used method for training AI by trial and error that improves the strategy in small, safe steps; it was the workhorse behind training chatbots like ChatGPT with human feedback. (PPO, 2017), a simpler policy gradientpolicy gradient, n.: A family of methods that improve an AI's strategy directly: make actions that led to good results a bit more likely, and actions that led to bad results a bit less likely. method that became the default for deep reinforcement learningdeep reinforcement learning, n.: Reinforcement learning in which a large neural network does the learning, letting an AI learn tasks such as video games or robot control directly from raw inputs like screen pixels or camera images. and for the reinforcement learning from human feedbackreinforcement learning from human feedback, n.: A way of training AI using people's judgments: humans compare pairs of answers, a scoring model learns their preferences, and the AI is then trained to produce answers that score well. used to train InstructGPT and ChatGPTChatGPT, prop. n.: OpenAI's AI chatbot, released free to the public in November 2022, which answers questions, writes and converses in everyday language. Its sudden popularity began the current AI boom.. He led OpenAI's reinforcement-learning team and later its post-training work, and is often described as an architect of ChatGPT. He co-authored 'Concrete Problems in AI Safety' (2016). In August 2024 he left OpenAI for AnthropicAnthropic, prop. n.: An American AI company that makes the Claude chatbot and models. It was founded in 2021 by former OpenAI staff and puts particular emphasis on AI safety research., saying he wanted to concentrate on alignment research, and in February 2025 he joined Mira Murati in founding Thinking Machines Lab as its chief scientist.