Image from OpenAI's new model thinks deeply

OpenAI today announced o1, a new AI model series designed to "reason" through complex problems before responding. This release marks a shift in OpenAI's approach, moving beyond simply scaling up model size to fundamentally changing how AI systems process information.

What is o1?

o1 represents OpenAI's first model family explicitly trained to spend more time deliberating on queries before outputting responses. The initial release includes two models:

  • o1-preview: The full-scale reasoning model
  • o1-mini: A smaller, cheaper variant optimized for coding and STEM tasks

OpenAI claims o1 can "reason through complex tasks and solve harder problems than previous models in science, coding, and math." The company says o1-preview performs comparably to PhD students on challenging benchmark tasks in physics, chemistry, and biology (a bold claim, if true).

Key capabilities touted by OpenAI include:

  • Complex code generation and debugging
  • Advanced mathematical problem-solving
  • Comprehensive brainstorming for multifaceted issues
  • Detailed document comparison and analysis
  • Instruction following for intricate workflows

How o1 differs from GPT-4o

The core difference behind o1 lies in its training methodology. While GPT-4o and previous models were trained primarily to predict patterns in vast text datasets, o1 utilizes reinforcement learning to develop problem-solving skills.

OpenAI's research lead Jerry Tworek stated: "o1 has been trained using a completely new optimization algorithm and a new training dataset specifically tailored for it." This approach teaches the model to refine its thinking process, experiment with different strategies, and identify mistakes.

The result is a model that mimics human-like deliberation, employing a "chain of thought" to work through problems step-by-step. This manifests in the model's outputs, with o1 often using phrases like "I'm curious about," "I'm thinking through," and "Ok, let me see" to structure its reasoning.

Technical differences:

  1. Training approach. o1 uses large-scale reinforcement learning, optimizing for successful problem-solving rather than pure pattern matching.
  2. Reasoning pipeline. o1 implements a multi-step reasoning process before generating final outputs, allowing for more complex problem decomposition.
  3. Specialized datasets. Training data for o1 was curated to emphasize reasoning tasks, particularly in STEM fields.
  4. Performance tradeoffs. o1 sacrifices speed and broad knowledge for improved reasoning capabilities in specific domains.
  5. Model architecture. While details remain limited, OpenAI likely modified the underlying architecture to support the new reasoning pipeline.

Technical deep dive

Chain-of-thought reasoning

The cornerstone of o1's architecture is its implementation of chain-of-thought reasoning. This process involves: