Physical Contradiction

Last updated July 1, 1997

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Contents

• Intensifying the Contradiction
  • The concept of a physical contradiction
  • Separation of features
  • Separation in space
  • Separation in time
  • Separation in structure
  • Exercise 1
  • Exercise 2
• Innovative Crossword
  • A crossword analogy
  • Systematic and intuitive thinking
  • Second summary
• The Richness of the Ideal Final Result
  • Multiple properties of The Ideal Final Result
  • Two is better than one
  • Features instead of technologies
  • How ideal is a two story city?
  • Exercise 3

Intensifying the Contradiction

Physical contradiction. If we consider more carefully our examples we see that we
are dealing not only with alternative, but with opposite systems. An "open" frame is light,
but donīt provide weather protection. A frame, consisting of air alone, is maximally light,
but donīt protect at all. We can intensify the conflict saying that the frame should be
gaseous, to be light, and solid, to protect from rain. What could be, in some sense, gaseous
and solid at the same time? Maybe the first thing one remembers is foam.
Letīs transform our matrix:

System	Weight	Waterproofness
Gaseous frame	+ leight	- "leaking"
Solid frame	- heavy	+ "tight"
Foam frame	+ leight	- "tight"

The matrix contains actually not one, but two contradictions. Engineering contradictions
are conflicts between two different variables or requirements. Improving the parameter
"weight" we worsen the other parameter "waterproofness". Weight and waterproofness
ARE physically totally different variables. The conflict "gaseous - solid" means
that the same variable - density - should have different, incompatible values.

A situation when some variable should have two different values in the same place at
the same time, is called physical contradiction. Physical contradiction is the situation not
possible in reality. It is a useful model. When we find not only the engineering contradiction,
but the physical conflict, too, weīll have much more chances to find interesting ideas.

Separation of features. The formulation "in the same place at the same
time" gives already a clue. If not in the same place, maybe in different places?
If not at the same time, maybe at different times? But what to do if the opposite
properties should be realized in the same place and at the same time? We can give
to "micro-level" particles of the system, and to the "macro-system", system as
whole, opposite properties. Foam is gaseous on micro-level, solid on macro-level.
So there is three ways to separate features of properties:
- separation in space
- separation in time
- separation in structure

Separation in space. The chain transmission of the bike is a good example
of the separation in space. Before the invention of transmission cyclists met two contradictions:
To get high speed one needs a large wheel, to ride comfortably - a small one. The other
contradiction: to get high speed the cyclist should rotate pedals with high revs, which again
is uncomfortable. A chain solved both contradictions. A small chainring was separated in space
from a large wheel. A low speed of rotation in the chainring was separated in space from high
speed of rotation in wheel. It became possible to make a wheel smaller.

Separation in time. The collapsible bike is an example of separation in time:
big size during riding, small size during the transport. Burning of waste is a crude example of
changing properties in time by chemical reactions. More sophisticated examples are biologically
dissolvable materials. For example a soluble bone nail, which makes unnecessary an extra
operation for removing a nail.

Separation in structure. We presented foam as example of separation properties
in structure. Another example: a soft polishing disc with hard, abrasive particles. Or ultrasound
and cavitation in the liquid. Local pressures and temperatures can be very high, although
the liquid as whole has norma pressure and temperature.

It is important to note that often the problem changes during the solution work. In the beginning
we had a conflict between weight and waterproofness. In the end we got the problem: how to
combine gaseous and solid substance.

The physical contradiction is usually a turning point in problem solving. Experience has
shown that just here new ideas begin to appear. When you have an contradiction, try to
intensify it to physical contradiction. Then try to solve the contradiction by one of three ways,
or by all three ways. Letīs repeat the avenues to ideas:
- separation in space
- separation in time
- separation in structure

Exercise 1. Consider previous excercises and examples you have collected.
Check the formulations. Intensify the conflict to the physical contradiction.

Exercise 2. Study previous excercises. Define the type of contradiction and
corresponding features of the ideal final result.

Innovative Crossword

Filling up crossword we use common and ease words to find the difficult ones. Working with
the matrix we use existing information to find new ideas (and problems!).

Systematic and intuitive thinking. The matrix, as well as crossword, combines
beautifully a systematic research and an intuitive envisioning. A good crossword has only one
right solution. Words and pictures have rigid links. In this sense filling up a crossword is
very systematic work. But at the same time the work is rather chaotic and intuitive. You
can write words in any order, erase them and write again. The crossword helps to recall
new words from subconsciusness.

Analogically, you can move in the two pluses matrix in any direction. But the parts of the
matrix: pluses, minuses, systems and ideal final result, should correspondend each other.
The matrix boosts intuition. Already filled cells help to see new features immediately.

Second summary. The simple two pluses matrix contains much
information and many important design principles:
- Engineering contradiction. Try to find contradiction. Donīt avoid it.
- Physical contradiction. Intensify contradiction. Donīt try to smooth it.
- Ideal final result. The goal is to remove a contradiction, not compromise
- Alternative system. Define alternative system with opposite pluses and minuses
- Feature transfer. The best features should be combined, usually not systems themselves
- Bisystem. The result is better, if you consider two systems instead of a one prototype

The Richness of the Ideal Final Result

Multiple properties of The Ideal Final Result. In the beginning we said shortly,
that the Ideal Final Result (abbreviated IFR) combines the pluses of the original systems,
but their disadvantages disappear. No weīll substantially widen the concept of the IFR.
We have already seen that the physical contradiction, not only engineering one, should
be removed. The system should not become more complicated. New disadvantages
should not be introduced.

When the above-mentioned requirements are fulfilled, the ideality of the system is increased.
In the literature on problem solving ideality is defined as benefits relative to cost factors:

Ideality = Benefits / (Costs+Harm)

The definition is very similar to the definiton of the value in Value Analysis:

Value = Function/Cost

The difference is that in TRIZ the concept of ideality contains many requirements additional to
to the function-cost-relation. Letīs list most important characteristics of the Ideal Final Result:

1. The features of alternative systems are combined
2. Engineering contradictions are solved
3. The physical contradiction is solved
4. The advantages of original systems are preserved
5. The deficiencies of original systems are eliminated
6. The system doesnīt become more complicated
7. New disadvantages are not introduced
8. The ideality or value of the system is increased
9. Costs are decreased
10. Competitiveness is improved

It is important to check all characteristics when the solution is evaluated. If some criteria
will not be fulfilled, there is a new problem which shall be solved.

Two is better than one. We consider two alternative systems. The ideal final result combines the
good features of both initial systems. So we can call the ideal final result
bisystem. When we have an engineering contradiction, we always have a bisystem, too. It is
usually easier to improve two alternative systems than one prototype, or "monosystem". We
can say: "Find the contradiction and solve it." Or we can say: "Find two alternative systems.
Combine the best features of the alternatives, and remove drawbacks." Both statements are
true. A"bisystem model" is often simply more clear than a "contradiction model".

Features instead of technologies.The ideal system incorporates features
of two initial ones. Two story city combines features of a "car street" and a sidewalk. A
"smart paper" or an electronic "reading device" combines features of a book and a disk. The
incorporation of good features from other systems to the initiatial one is called feature transfer.
The Ideal Final Result concentrates attention to feature, important to users and customers.

How ideal is the foam frame? Letīs compare the idea of with
general requirements of the IFR:

1. The features of alternative systems: common frame AND body-shell , OK
2. Engineering contradictions: more light AND more water-proof , OK
3. The physical contradiction: gaseous AND solid, OK
4. The advantages of original systems: lightness and waterproofness are preserved, , OK
5. The deficiencies of original systems: heavy frame and "leaks" disappear
6. Do the system become more complicated: problems of manufacturing?
7. New disadvantages: maneuvrability of body-shell?
8. The ideality or value of the system: is increased partially
9. Costs: may be a problem, necessary to seek ways to decrease costs
10. Competitiveness: considerable

Exercise 3. Check the ideas you have get in earlier exercises against the
the requirements of the IFR.

1. The features of alternative systems:
2. Engineering contradictions:
3. The physical contradiction:
4. The advantages of original systems:
5. The deficiencies of original systems:
6. Do the system become more complicated:
7. New disadvantages:
8. The ideality or value of the system:
9. Costs:
10. Competitiveness:

Further reading

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