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+# CORPUS-0015
+## Materials Can Change Value Through Use
+### Status: Training Corpus Seed
+### Layer: Layer_0--Primitive_Facts
+### Purpose: Teach that a material's value depends partly on what it can become, not only on what it is now
+### Repository Path: docs/training/corpus/Layer_0--Primitive_Facts/CORPUS-0015-materials-can-change-value-through-use.md
+
+---
+
+## 0. Principle
+
+A material's value depends partly on its possible uses.
+
+The same raw material can have different value depending on:
+
+- who needs it
+- what it can become
+- how soon it is needed
+- what tools or skill are available
+- what other materials are scarce
+- whether the intended use changes
+
+A plank is not only a plank.
+
+It may become a roof beam, cart repair, tool handle, bridge part, hull plank, scaffold, crate, or military component.
+
+---
+
+## 1. Roman-Visible Example
+
+A trader sees timber stored for ordinary construction.
+
+Then he hears that carts are breaking, boats need repair, and a contractor is seeking straight dry boards.
+
+The timber has not changed physically.
+
+But its value may change because its best use has changed.
+
+Construction timber may become more valuable if redirected into:
+
+- cart parts
+- wheel stock
+- ship repair
+- bridge repair
+- tool handles
+- temporary structures
+
+The material's future use alters its present value.
+
+---
+
+## 2. Minimal Use-Value Structure
+
+Material value depends on at least:
+
+1. material type
+2. quality
+3. quantity
+4. current owner
+5. possible uses
+6. scarcity of substitutes
+7. available craftsmen
+8. urgency of demand
+9. cost of transformation
+10. distance to the buyer or workshop
+
+A material's value is not fixed only by its original purpose.
+
+---
+
+## 3. Incorrect Modern Assumption
+
+Incorrect assumption:
+
+> A material has one value because it has one intended use.
+
+Correction:
+
+> A material may gain or lose value when conditions make another use more urgent, scarce, or profitable.
+
+The trader must ask not only what the material is, but what it can become.
+
+---
+
+## 4. Simulation Use
+
+This principle supports:
+
+- raw material valuation
+- substitution
+- production chains
+- emergency demand
+- scenario chaining
+- workshop shortages
+- military or civic procurement
+- route cargo selection
+- speculative buying
+
+The model should not treat goods as locked permanently to their original category.
+
+---
+
+## 5. Canonical Test
+
+If the model sees:
+
+> Timber is stored for construction.
+
+It must ask:
+
+- what quality is the timber?
+- is it dry or green?
+- is it straight, curved, thick, or narrow?
+- what else can it become?
+- who urgently needs that alternate use?
+- what craftsmen can transform it?
+- what would transformation cost?
+- is the alternate use worth more than the original use?
+
+Only then can the material's value be evaluated.
+
+---
+
+## 6. Success Condition
+
+If the model stops treating materials as single-purpose goods and starts evaluating what they can become under current conditions, this file is functioning correctly.