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Theory of Inventive Problem Solving (TRIZ) 293

1. Increasing benefits.
2. Reducing costs
3. Reducing harms
4. Benefits increasing faster than costs and harms

In terms of TRIZ, any technical system or product is not a goal in
itself. The real value of the product/system is in its useful functions.
Therefore, the better system is the one that consumes fewer resources
in both initial construction and maintenance. When the ratio becomes
infinite, we call that the “Ideal final result” (IFR). Thus, the IFR sys-
tem requires no material, consumes no energy and space, needs no
maintenance, and will not break.

9.2.4 Contradiction
In the TRIZ standpoint, a challenging problem can be expressed as
either a technical contradiction or physical contradiction.

Technical contradiction. A technical contradiction is a situation in
which efforts to improve some technical attributes of a system will lead
to deterioration of other technical attributes. For example, as a con-
tainer becomes stronger, it becomes heavier, and faster automobile
acceleration reduces fuel efficiency.
A technical contradiction is present when

■ The useful action simultaneously causes a harmful action
■ Introduction (intensification) of the useful action, or elimination or
reduction of the harmful action causes deterioration or unacceptable
complication of the system or one of its parts

A problem associated with a technical contradiction can be resolved by
either finding a trade-off between the contradictory demands or over-
coming the contradiction. Trade-off or compromise solutions do not elim-
inate the technical contradictions, but rather soften them, thus retaining
the harmful (undesired) action or shortcoming in the system. Analysis of
thousands of inventions by Altshuller resulted in formulation of typical
technical contradictions, such as productivity versus accuracy, reliability
versus complexity, and shape versus speed. It was discovered that
despite the immense diversity of technological systems and even greater
diversity of inventive problems, there are only about 1250 typical system
contradictions. These contradictions can be expressed as a table of contra-
diction of 39 design parameters (see Table 9.1 and the chapter appendix).
From the TRIZ standpoint, overcoming a technical contradiction is
very important because both attributes in the contradiction can be