TRIZ — Theory of Inventive Problem Solving

Genrich Altshuller, 1946–. Soviet engineering invention method derived from analysis of hundreds of thousands of patents. 40 inventive principles + contradiction matrix + Ideal Final Result. Used by Samsung, Intel, Boeing, P&G.

Core principle

Most inventive problems are technical contradictions: improving X degrades Y. The trade-off is usually an artifact of how the system is decomposed, not a fundamental constraint. Solve by identifying the contradiction explicitly, then applying principles that have historically resolved similar contradictions in patent literature.

The Ideal Final Result: the desired function performed without the system that performs it (the system has, in some sense, eliminated itself). Use as target.

When to use

• Engineering / mechanism / device invention
• Measurable parameter conflict (mass/strength, cost/reliability, speed/accuracy)
• You suspect the trade-off is fake
• Group brainstorming with non-arbitrary structure

Don't use when

• Artistic, social, or expressive problems (TRIZ requires measurable parameters)
• Your "contradiction" is preference, not parameter ("modern but classic" is not TRIZ)
• A textbook fix exists; TRIZ is for inventive problems

The 40 inventive principles

1. Segmentation — divide into independent parts, increase divisibility
2. Taking out — extract the disturbing part; separate only what's needed
3. Local quality — make different parts have different properties
4. Asymmetry — replace symmetrical with asymmetrical
5. Merging — bring identical/similar objects closer; parallelize operations
6. Universality — one part performs multiple functions
7. Nested doll — place objects one inside another (matryoshka)
8. Anti-weight — compensate weight by combining with lift / hydro/aerodynamic forces
9. Preliminary anti-action — preload with opposite stress
10. Preliminary action — perform required action in advance
11. Beforehand cushioning — emergency means in advance
12. Equipotentiality — change conditions so object need not be raised/lowered
13. The other way round — invert action; movable parts fixed and vice versa
14. Spheroidality / curvature — replace linear with curved; flat with spherical
15. Dynamics — make rigid moveable; let parts shift configuration
16. Partial or excessive actions — slightly less or slightly more if 100% is hard
17. Another dimension — move 1D→2D→3D; tilt; use the other side
18. Mechanical vibration — oscillate, ultrasonics
19. Periodic action — periodic instead of continuous; vary frequency; pauses
20. Continuity of useful action — eliminate idle running
21. Skipping — perform fast through dangerous stages
22. Blessing in disguise — use harmful factors to obtain a positive effect
23. Feedback — introduce or modify feedback
24. Intermediary — use an intermediary article or process
25. Self-service — make the object service itself; use waste resources
26. Copying — cheap copies instead of fragile/expensive originals
27. Cheap short-living — disposable instead of durable
28. Mechanics substitution — replace mechanical with sensory (optical, acoustic, EM)
29. Pneumatics and hydraulics — replace solid with gas/liquid; inflatable
30. Flexible shells and thin films — instead of 3D structures
31. Porous materials — make porous; use pores to introduce useful substance
32. Color changes — change color or transparency
33. Homogeneity — interacting objects from same material
34. Discarding and recovering — portions disappear after use; restore consumables
35. Parameter changes — physical state, concentration, density, flexibility, temperature
36. Phase transitions — exploit phenomena at phase changes
37. Thermal expansion — different coefficients of thermal expansion
38. Strong oxidants — oxygen-enriched, ozonized
39. Inert atmosphere — inert environment or vacuum
40. Composite materials — uniform → composite

Procedure

1. State the contradiction in the form: "I want X to improve, but X improvement causes Y to degrade." If you can't state it crisply, you don't yet have a TRIZ problem.
2. Compare to Ideal Final Result. What would it look like if the system eliminated itself?
3. Look up candidate principles. The contradiction matrix at triz40.com maps (X parameter, Y parameter) → recommended principles. Or scan the 40 above for fits.
4. Translate principle to mechanism. A principle is general; the mechanism is specific to your situation.
5. Compare candidates against IFR. Pick closest.

Worked example

Problem: fast brew time (under 60s) vs full extraction (typically 4 min). Contradiction: speed vs completeness of extraction. Candidate principles: 1 (Segmentation), 17 (Another dimension), 19 (Periodic action), 35 (Parameter changes). Translations:

• Segmentation: pre-extract concentrates; dilute on demand. (Nespresso.)
• Another dimension: extract under pressure (espresso).
• Periodic action: pulse-extract with pauses (some pour-over).
• Parameter changes: brew at different temperature/pressure (cold brew = low T long time; espresso = high P short time).

IFR comparison: closest to "no brewing time" is pre-extracted concentrate (Segmentation). Resolves the contradiction by separating extraction from delivery in time.

Anti-slop notes

• Don't present the 40 principles as a generative checklist — that's SCAMPER. TRIZ's value is the contradiction lens + patent-derived priors.
• Translate principle to mechanism, don't stop at the principle name.
• Don't claim TRIZ where it doesn't apply (artistic, social, preference contradictions).
• Don't invent principles in Altshuller's style.

Tools: triz40.com (interactive matrix). Source: Altshuller, And Suddenly the Inventor Appeared (1994).