lev-os TRIZ Inversion (Principle #13)
Overview
Inversion is one of Genrich Altshuller's 40 Inventive Principles from TRIZ (Theory of Inventive Problem Solving), derived from analysis of over 200,000 patents. The principle states: reverse or invert the action used to solve the problem, or make stationary parts movable and movable parts stationary.
Inversion appears in three forms:
- Action Inversion - Do the opposite of the expected action
- Property Inversion - Reverse the property (hot to cold, push to pull)
- Perspective Inversion - Turn the object or viewpoint upside down
The underlying insight: when conventional approaches fail, the solution often lies in doing the exact opposite. What seems counterintuitive frequently unlocks breakthrough innovations.
When to Use
- Conventional solution attempts have reached diminishing returns
- The standard approach creates unintended negative consequences
- Physical constraints prevent the obvious solution
- You need to break mental fixation on a single approach
- The problem involves getting something out of a tight space
- Heat, force, or pressure applied normally doesn't work
- You need to question fundamental assumptions about how things "should" work
The Process
Step 1: Identify the Conventional Action
What is the standard, expected, or obvious way to solve this problem?
Example: To loosen stuck metal parts, heat the outer part to expand it.
Step 2: Invert the Action, Property, or Perspective
Ask: what if I did the exact opposite?
- Action Inversion: Instead of heating, try cooling
- Property Inversion: Instead of expanding, try contracting
- Perspective Inversion: Instead of working from outside-in, try inside-out
Example: Cool the inner part instead of heating the outer part.
Step 3: Analyze Why the Inversion Works
Understand the physics, psychology, or logic of why the opposite approach succeeds.
Example: Cooling the inner part causes it to contract, creating clearance for removal.
Step 4: Test Edge Cases
Verify that the inverted solution works across expected scenarios and doesn't create new problems.
Example: Ensure cooling method doesn't damage materials or create condensation issues.
Step 5: Generalize the Inversion Pattern
Document the insight for future applications in similar contexts.
Example: "When expansion doesn't work, try contraction" becomes a reusable heuristic.
Example Application
Situation (Manufacturing Defect): Paint spray booth generates overspray waste that contaminates products and clogs filters.
Application:
- Conventional Action: Move paint toward the object
- Inversion: Make the object move to capture paint (electrostatic painting)
- Why It Works: Charged object attracts paint particles, reducing overspray by 30-40%
- Edge Cases: Requires conductive objects, managed humidity levels
- Pattern: "Instead of pushing substance toward target, make target pull substance"
Outcome: Reduced paint waste by 35%, improved finish quality, lower filter replacement costs.
Anti-Patterns
- Inverting without understanding why the original approach failed
- Applying inversion mechanically without considering context
- Ignoring safety implications of reversed actions (cooling with liquid nitrogen without ventilation)
- Assuming all problems have an inverted solution
- Over-complicating simple problems that don't need inversion
- Failing to test whether inversion actually improves the outcome
Related
- triz-asymmetry (break symmetry rather than maintain it)
- triz-taking-out (extract rather than add)
- reversal-method (de Bono's lateral thinking technique)
- first-principles-thinking (question assumptions before inverting)
- pre-mortem (invert success planning into failure analysis)