foundation

# Foundation: Building Fundamental Understanding

Build deep foundational understanding of a domain. Goes beyond surface definitions to explore **meaning**, **connectivity**, and **historical development** of concepts.

## Position in Learning Pipeline

```
domain-vocab → foundation → trace/frontier/paper-flow
(WHAT)         (WHY/HOW)    (WHERE)

Concepts  →  Understanding  →  Research Origins
```

## When to Use

- "Build foundation for [domain]"
- "I know the terms but don't understand how they connect"
- "Foundation [domain]"
- "[domain] fundamentals deeply"
- "How did [domain] develop?"
- "What's the big picture of [domain]?"
- After domain-vocab, before diving into papers

## When NOT to Use

- Just need term definitions → use `domain-vocab`
- Want specific paper lineage → use `trace`
- Want latest research → use `frontier`
- Want full concept + paper treatment → use `deep-dive`

## Core Value

> Knowing terms is vocabulary. Understanding how they connect, why they exist, and how they evolved is fluency.

Foundation transforms scattered concepts into a coherent mental map.

## Workflow

### Phase 1: Deep Meaning Extraction

**Objective:** Go beyond dictionary definitions to understand what terms really mean.

**Actions:**
1. For each key concept, extract:
   - **Literal meaning**: What the term denotes
   - **Connotative meaning**: What practitioners imply when using it
   - **Historical meaning**: How the meaning evolved over time
   - **Contextual meaning**: How meaning shifts in different sub-domains

2. Identify semantic layers:
   - Surface level (beginner understanding)
   - Working level (practitioner understanding)
   - Deep level (expert/researcher understanding)

**Output:**
```yaml
concept: "Gradient Descent"
meanings:
  literal: "Iteratively moving in the direction of steepest decrease"
  connotative: "The workhorse optimization method; implies iterative refinement"
  historical:
    - 1847: Cauchy introduces for equation solving
    - 1960s: Applie