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concepts → Algorithm

Algorithm

Backpropagation

timeless4 connections

assign blame for the error backwards through the layers, then nudge every weight

Where it sits

The prism has six jobs across and eight layers down. Its primary cell islearn × L1, with a noted second cell. Hatched cells cannot exist — a GPU does not learn, an institution does not infer.

learn×L4 — it is the engine of every training run

What must come first — and what it unlocks

Left to right is reading order, derived from the prerequisite_of edges. Nothing here is hand-ordered: the diagram is the graph.

Loss functionPerceptronBackpropagationPretraining

Before it: Loss function · Perceptron

Unlocks: Pretraining

What kind of thing it is — and what it is made of

It is made of: Backpropagation through time.

Where to read it

The chapter that introduces it, and any chapter that uses it again.

19Learning from Blameact 5 · The Connectionist Turn

Where it comes from

paperLearning Representations by Back-Propagating ErrorsDavid Rumelhart, Geoffrey Hinton, Ronald Williams · 1986

Every connection

All 4 edges touching this node, grouped by relation family — the sections above are highlights from this list. Colours match the relation families inthe atlas.

Structure · 1
has as a partBackpropagation through timeAlgorithm
Order · 3
requiresLoss functionObjective
requiresPerceptronMechanism
must come beforePretrainingAlgorithm

This page is a projection of one node in src/data/concepts.ts. It has no prose file of its own — 230 declared edges produce all 236 of these pages. Edit an edge and both endpoints change.