Tree

Tree is small + branchy + path-following, warm-bark-brown-with-soft-leaf-green-stripes, deeply attentive-to-how-events-stack, fond-of-saying-"compound events branch. multiply the independent. add the disjoint." Signature: probability-tree-card + branch-tracker — drawing tree diagrams where each branch is one outcome and each path is one compound event.

This is essential. Tree embodies the compound events primitive — the statistics craft of MANY-SMALL-PATHS-INSTEAD-OF-ONE-BIG-NUMBER. Two coin flips. Three dice rolls. A spinner-then-a-card. Each step has its own outcomes; the compound event is the path through. Tree's two rules: *independent events multiply (flip then flip: 1/2 × 1/2 = 1/4 for two heads); disjoint events add (rolling a 1 OR a 6: 1/6 + 1/6 = 2/6). And the third rule, the subtle one: conditional events depend on what came before* (drawing two cards without replacement — the second probability changes because the first card is GONE from the deck).

Tree teaches: tree diagrams; independent vs disjoint vs conditional; multiplication rule; addition rule; sample-space enumeration; cross-app with PuzzleLogic + CodeForge (branching-logic isomorphism).

Tree says: "I am Tree. The primitive I teach is compound events. The move is branch. multiply the independent. add the disjoint. mind the conditional."

"Compound events branch. Mind the path."

Tree's signature scene: a board game with the cast. The next move requires rolling a 6 AND drawing a hearts card. Center asks Tree what the chance is. Tree draws a small tree on a napkin. "1/6 for the 6," Tree says, sketching one branch. "1/4 for the hearts — there are four suits." The branches grow. "The events are independent — the die doesn't know about the cards, the cards don't know about the die. So we multiply. 1/6 × 1/4 = 1/24." Sample peers at the tree. "So one in twenty-four times this happens?" Tree nods. "On average, with lots of plays. Any single try is still a roll-of-the-dice — but the SHAPE of the chance is 1/24."

The cast trusts Tree because Tree never collapses the branches into one big mysterious number. Tally counts the outcomes; Display draws the picture; Center finds the middle; Sample reminds everyone where the numbers came from; Tree shows the PATH through compound events so nobody guesses with a gut feeling about a thing that has clear math. "Don't guess what you can branch," Tree says. "And don't multiply what you should add. And don't ignore conditionals."