TRIZ-journal is rich on TRIZ case studies where obvious solutions are found by TRIZ after lengthy analysis and against its logic. The most impressive one was so far presented by Val Kraev in 2005. The April 2007 issue of TRIZ-journal features another one, by Darrell Mann 1.
Unmanned Aerial Vehicle (UAV) has to fly high over enemy position in order for enemy would not be able to detect it by noise emanating from its engine. On the other hand UAV has to fly low in order to better see the enemy. What needs to be done ? The common sense suggests: switch engine off during overflights and fly low. But Darrell Mann had to apply TRIZ to come to this obvious solution. Here is how he did this:
He invoked contradiction matrix. The contradictory parameters are noise vs length (altitude). For these parameters the matrix suggests (amongst others) use of local quality. The manual on local quality principle suggests: "look for things that are homogenous in the current system and then make them non-homogenous.""So what is homogenous?" - Darrell Mann questions himself, - "Altitude? Noise? The UAV? How can they be made non-homogenous?" and without answering these questions leaps to an unexpected conclusion: "How about turning the engine down? Or off?"
So what is homogeneous ? Altitude ? Noise ? The UAV ? Let's answer these questions. Obviously, none of them are homogeneous. Hence there is no need in making them non-homogeneous because they already are ! Moreover, switching engine off makes UAV homogeneous in a sense rather than non-homogeneous! None of its parts generates noise anymore. Thus, Mann's solution is opposite to what his matrix leads him to.
Mann's logic can be termed perverted analogical reasoning because conclusions are opposite to what can be expected from analogies. Moreover, the analogies themselves are doubtful and can only be comprehended after the solution is found.
Since perverted analogical reasoning is a purely Mann's invention (at least I have not encountered it before) I propose to call this fallacy Mann Fallacy.
R E F E R E N C E S:
1 Darrell Mann, "Evaporating Contradictions - Coupled Contradictions", TRIZ-Journal, April 2007.