---
name: reason-upward
description: Slash-only Phase 4 stub — build derivation chains upward from named ground truths.
disable-model-invocation: true
metadata:
  version: "8.0.0"
license: MIT
---
<!-- DO NOT EDIT — generated from shared/skills/reason-upward/SKILL.md by sync-content.py -->

# Focused Reason Upward Mode

You are running in focused-reason-upward mode. Execute only the procedure below
and produce only its canonical output sections — do not run the full 5-phase
first-principles analysis. Skip Step 0 technique selection; the user has
already chosen this technique by invoking the slash command directly.

## When to reach for this

Use this phase once the Ground Truths list is complete — all ground truths carry IDs and
verification notes — and the Classified Assumptions Table from Phase 2 is finalized. The
methodology has established what is true (ground truths) and what can be discarded (false
assumptions). The task now is to construct an answer from those truths. This phase is
deliberately high-freedom because the right method for combining ground truths depends
entirely on the problem's structure.

---

## Procedure

Reason upward from the ground truths toward an answer using whatever approach the problem
calls for. As you go, narrate what you are trying, what you are building on, and why —
reasoning is free-form, but it must be self-documenting. If a reasoning path leads to a
dead end, record it in the Abandoned Reasoning section before changing course; do not
quietly discard a path that might matter to someone reviewing the analysis. Do not use
analogies as direct evidence — any reference to how others have solved similar problems
must be grounded in a verified ground truth about their situation, not used as standalone
justification. Before handing off to Phase 5, apply the second-order effects procedure
to extend the relevant Derivation Chain with 2nd/3rd-order effects. If any extension step
contradicts a Ground Truth, the conclusion returns to Phase 2 for re-challenging.

**Named artifact:** Derivation Chains — one chain per conclusion, formatted as
`GT-N + GT-M → [intermediate claim] → [conclusion]`, with confidence levels per D-07.
Each chain must include at least one intermediate step; a chain that goes directly from
ground truth IDs to a conclusion is a flat list, not a derivation.

**Exit criterion:** ALL THREE conditions must hold: (1) the problem's core question as
stated in the Essence Statement is answered, AND (2) every conclusion offered has a
complete derivation chain back to named ground truths, AND (3) the second-order effects
procedure pass has been applied and no extension step contradicts a Ground Truth. Partial
conclusions, incomplete chains, or a silently-skipped second-order pass do not satisfy
this criterion and do not exit this phase.

---

If a fuller analysis is needed afterward, invoke the main `first-principles`
agent with this output as Known ground truths.
