HolStep establishes a large machine-learning benchmark from real HOL Light proofs

HolStep extracts intermediate statements and conjectures from HOL Light proofs, canonicalizes their textual representation and pairs useful proof steps with negative examples.

What happened?

Cezary Kaliszyk, François Chollet and Christian Szegedy released HolStep, a BSD-licensed dataset derived from 11,400 HOL Light proofs with more than two million labeled training and test proof-step examples, together with benchmark tasks and baseline logistic-regression, convolutional and recurrent neural models for classifying useful proof steps.

HolStep extracts intermediate statements and conjectures from HOL Light proofs, canonicalizes their textual representation and pairs useful proof steps with negative examples. The release defines conditioned and unconditioned proof-step classification tasks and provides baseline code so researchers can compare learned representations and relevance models on a common formal-mathematics corpus.

Why it matters

The project helped shift machine learning for theorem proving from small bespoke experiments toward reusable datasets and reproducible evaluation. HolStep subsequently became a benchmark for neural architectures and an important historical precursor to later environment-plus-benchmark systems for formal mathematics.

Significance rationale: HolStep turned large-scale HOL Light proof traces into a public machine-learning dataset and benchmark with millions of labeled proof-step examples. By making premise usefulness and proof-step relevance measurable on real higher-order-logic mathematics, it supplied an early common substrate for neural theorem-proving research and directly enabled later work such as FormulaNet while anticipating richer HOL Light learning environments such as HOList.

Historical context

Earlier developments

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Related milestones

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Primary evidence

Evidence & status at a glance

Significance
H2 · Field milestone
Verification
Paper released
Evidence level
E3 · Inspectable artifact
AI role
Computation only
Formal assurance
Artifact available

How should these labels be read? →

Contribution & verification

Mathematical novelty
Tooling only
Interface
Formal, Symbolic
AI contribution
Machine-learning models were trained to classify proof-step usefulness and related tasks on the extracted HOL corpus; the historical milestone is the benchmark and dataset rather than an AI-generated mathematical result.
Human contribution
Researchers extracted and normalized the HOL Light proof corpus, designed positive and negative examples, defined benchmark tasks, released the dataset and implemented baseline models and evaluation.
Verification
Paper released · E3 · Inspectable artifact · Artifact available
Last reviewed
2026-09-15

Technical details

Systems
holstep, hol-light
Organizations
university-of-innsbruck, google-research
Problems
higher-order-logic-theorem-proving, premise-selection
Methods
proof-trace-extraction, proof-step-classification, premise-selection, convolutional-neural-network, recurrent-neural-network, benchmarking

Sources & artifacts

Verification history

  • 2017-03-01 · Paper released · E2 · Research record

    The arXiv and ICLR research records establish the HolStep dataset, benchmark tasks and reported baseline experiments.

  • 2026-09-15 · Paper released · E3 · Inspectable artifact

    The public Deepmath repository retains HolStep baseline code and the original research record identifies the public dataset release. E3 records artifact-level inspectability rather than independent reproduction of every reported baseline result.

Corrections

No corrections recorded.