Rafhael Oliveira · IA

Memory and horizon: two claims from LeCun that became experiments, and both hold for text

The persistent memory that crosses a whole window, and the abstraction that predicts further. Measured on a 7.4 M model.

1 min read· chapter: 10 min· Experiment in progress · chapter updated on 12 Sept 2026

Landed here from LinkedIn? This is chapter 11 of the experiment Antivision · Latent Rehearsal. It reads on its own; if you want the beginning, it is chapter 00.

LeCun says: each level of abstraction predicts further than the one below. We measured. It holds for text. Two of his claims became experiments. The first: combine perception with the content of a memory. An ordinary language model does not have that, it has the window. We added a memory vector that persists, and the memory of the right text predicted better than another text's memory even a whole window later. The second: the abstract level, which never saw the individual tokens, predicts the next block in one step with four times the gain of the token level rolled eight times. At the honest scale of a 7.4-million model.

The three points

  1. Memory: the right text's predicts better than another text's (0.173 against 0.193), and the one from a window ago is worth as much as the recent one. Persistence, not recency.
  2. The limit: the whole past is worth less than each half. Summed memory dilutes. It is what motivates chapter 14.
  3. Horizon: level 2 in one step gains +0.078 over the floor; level 1 rolled eight times gains +0.020. Abstraction predicts further, four times.

From the chapter, the beginning

Two claims from LeCun that became experiments: "combine perception with the contents of a memory" and "each level of abstraction predicts further than the one below". Both were measured, and both hold for text — at the honest scale of a 7.4 M model.

LeCun lists persistent memory, in both talks, as a requirement of an intelligent system, and the talk says where it enters: perception gives only the current state; the full state is perception combined with the contents of a memory. An ordinary language model has no such thing — it has the context window, and what leaves it ceases to exist.

Keep reading chapter 11 →Ler em portuguêsThe PDFs by e-mail →
What the chapter covers · 2 sections · 10 min
  1. Persistent memory
  2. Horizon: does abstraction predict further?
All chapters of the experiment · Antivision · Latent Rehearsal
  1. 00 · Antivision: an ELLM, a language model that rehearses in latent space before speaking
  2. 01 · The custom tokenizer: why 16 thousand tokens suit this corpus better than 50 thousand, and what the whole table shows
  3. 02 · Two architectures, one file: the fair duel between 2019 and what came after
  4. 03 · The geometry of the embedding: training starts with a perfect space and ruins it
  5. 04 · The lineage of collapse: five answers from computer vision, each measured on text
  6. 05 · The rudder and the world model: three versions of the same question, each measured against the last
  7. 06 · Method and mistakes: the rules of a legitimate comparison and the catalogue of our own errors
  8. 07 · Scale and budget: what it costs to reach GPT-3, and why VRAM is almost never the limit
  9. 08 · The workbench: serve, x-ray and train from the browser
  10. 09 · The hierarchical architecture: the whole project aligned to the four patterns of the world model
  11. 10 · What JEPA is, according to LeCun: two talks read concept by concept, and where each one applies
  12. 11 · Memory and horizon: two claims from LeCun that became experiments, and both hold for text
  13. 12 · Learned costs and inference modes: the three searches and the two sources of energy, measured
  14. 13 · The corrections from LeCun's talks: failure, passage, flag, measurement
  15. 14 · Consulted memory: a bank of abstract states read by attention
  16. 15 · What it costs and what it delivers: us, GPT-1 and GPT-2 on the only ruler valid across tokenizers
  17. 16 · The minimum was off the list: the day I measured my own search by energy
  18. 17 · ELLM: the right name for a language model that predicts in latent space and decides by energy
  19. 18 · Searching better does not fix the energy: three searches, the same text
  20. 19 · The inversion that did not repeat: the world model's cost appears once the ruler stops swinging
  21. 20 · What changed on 17/09: two new chapters and two corrections

Before this: the GPT-2 course

Rafhael Oliveira
Rafhael Oliveira

Writes the GPT-2 course and runs the Antivision experiment, measuring every run before publishing the number. The LinkedIn posts start here and end in the chapters.

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