Definition
Plain language
A trick for solving a chain of dependent calculations fast by having everyone guess at once and then revise together, instead of waiting in line one at a time.
As stated in the literature
A classical iterative method that updates all unknowns in parallel from the previous round's values; exploited in APLR so that after K parallel passes the first K causally-ordered latent slots are exactly correct.
Why it matters: It turns a strictly sequential calculation into a parallel one, which is what lets a model refine many reasoning steps at the same time rather than waiting through each.
For example, instead of solving for each unknown in turn, everyone plugs in last round's guesses simultaneously and then refines, like a group filling in a crossword by guessing all answers at once and correcting overlaps.
Heard on the show
“And once you see that, you can borrow a trick that's been sitting in numerical methods for over a century — Jacobi iteration.”Episode 115 — Teaching a Phone Agent to Reason Silently, And Keeping It Honest