Paper: Language Is an Insufficient Substrate for Quantitative Reasoning
- Field: Machine Learning
- Authors: Reuben Vandeventer, David Imrem, David J. Wild
- Published: 2026-09-15
- arXiv: 2609.12105
- The prevailing assumption in applied machine learning is that progress on consequential quantitative decisions—such as pricing risk, allocating capital, triaging patients, or containing a network intrusion—will follow from progress in large language models (LLMs).
- A language model is trained on a representation of the world produced by human description. Description is a lossy encoding of the quantitative record, and the loss is irreversible: no downstream model, at any scale, can recover from a description what the description did not encode.
- The authors formalize this as a property of the representation on which a model is trained, rather than a property of model capacity—meaning scaling alone cannot fix the problem.
Key points
Three properties a language substrate cannot provide
Consequential settings demand three properties of a model that a language substrate cannot supply by construction:
1. Reproducibility 2. Lineage — every output traceable back to the source records that produced it 3. Calibrated uncertainty
Conclusion
These properties define a distinct model class, which the authors call Large Quantitative Models (LQM)—models trained directly on quantitative records rather than on human descriptions of them.
Original abstract (excerpt)
> The prevailing assumption in applied machine learning is that progress on consequential quantitative decisions such as pricing risk, allocating capital, triaging patients, or containing a network intrusion will follow from progress in large language models (LLMs). A language model is trained on a representation of the world that was produced by human description; description is a lossy encoding of the quantitative record, and the loss is irreversible: no downstream model, at any scale, can recover from a description what the description did not encode. We formalize this as a property of the representation on which a model is trained rather than of the model capacity, and we identify three further properties that consequential settings demand of a model and that a language substrate cannot...