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Physical Contradictions & 27 Windows

Physical Contradictions & 27 Windows

| On 29, Apr 2018

Darrell Mann

The physical contradiction aspects of the TRIZ method have become something of an orphan relative to other parts of the toolkit. Other tools have had lots of care and attention devoted to their upkeep and evolution in a changing world, whereas physical contradictions seem to receive a curt shrug of the shoulders from most. Maybe that might be because – as I know I’ve heard some original TRIZ researchers claim – the current form of the tool is already perfect. But then again…

Take the part of the process when the user has identified what they think might be a physical contradiction – “I want to focus light close up and I want to focus light in the distance”. In order to start the process of transition from problem to solution, the user is asked to think about three separation principles: can you separate the different requirements in space? Can you separate them in time? Can you separate them on condition?

These three strategies can be tested by asking ‘where?’, ‘when?’ and ‘if?’ questions. Where do you want to focus light close up? Where do you want to focus light in the distance? If the two answers are revealed to be different – “I want to focus light in the distance while looking up; I want to focus light close you while looking down” – then you have a good indication that, yes, this contradiction is amenable to, in this case, separation in space.

But from that point onwards, things seem to get somewhat blurry (if you’ll pardon the spectacle pun). Isn’t the looking-up/looking-down difference also about separation in time – “I want to focus light close when I’m looking down” – and also separation on condition – “I want to focus light close if I’m looking down (and reading)”?

More to the point does it matter? If I ask the three separation questions and they all reveal positive results, doesn’t that just mean I have more solution options? Doesn’t it mean we can progress to brainstorming through a long list of Inventive Principles faster?

I think the answer to all three questions is ‘yes’. Yes, we have more options, and yes we can start brainstorming faster. But yes it also matters that the where, when and if questions are unfocused and confusing. Is it good to get more options or is it better to have a clearer understanding of the problem? (Trick question – you should know by now that any question with the word ‘or’ in it is the wrong question.) The real point should be that we want the best of both worlds. If we’re able to solve a given physical contradiction by genuinely being able to use all three of the separation strategies, then great, but if we’re engineering the answer to the where, when and if questions using merely semantic arguments, we’re probably not doing ourselves any favours in terms of either understanding the real problem, or generating the most effective answers.

Case in point, sticking with the spectacles problem, bi-focals represent a common solution to the separation-in-space form of the physical contradiction problem, and switching between two pairs of glasses – one for reading and one for driving – is a common solution to the separation-in-time form of the contradiction, but we are only sensibly able to say one solution is better than the other depending on our specific context.

And ‘context’ here is the main issue to be addressed I believe. Is separation in space, time or condition better? It depends. And the best way to determine the dependency, we now think is to make use of the 9-Windows tool. Or rather a modified version of the long-established tool. The reason for the modification being that in its usual form the system-operator only allows us to explore the time and space dimensions:

Figure 1: 9-Windows Tool As A Physical Contradiction Separation Strategy Identifier

Looking for separation-related differences within and between pairs of windows offers a very thorough and structured means of identifying possible ways of separating two different physical contradiction conditions. But what about the ‘separation on condition’ possibility? How do we represent that using the 9-Windows?

Thinking about this question suggests that the 9-Windows are missing a dimension. We might hypothesize from the SI Pillars, that it might have something to do with ‘Interface’. In other words, the ‘between’s:

We want A if condition B.
We want -A if condition C.

Identifying what B and C are requires us to think about all of the possible conditional differences between what are in effect two measurements. So what to measure? And specifically, what is it we should be looking to measure that are different to ‘space’ and ‘time’ dimensions?

Measurements require systems. And systems require the presence of ‘fields’. Of which there aren’t that many types:

Perhaps these are the things we need to be looking for in order to test the ‘separation on condition’ option.

We want (the lens to be clear) if (UV level is below a threshold level).
We want (the lens to be dark) if (UV level is above a threshold level).
(As is the manner in which photochromic lenses usually work.)


We want (to focus close) if (IR signal is reflected in direction A).
We want (to focus distance) if (IR signal is reflected in direction B).
(As is the manner in which eye-tracking technologies usually work.)

The point being that the list of fields offers up a comprehensive set of conditional ‘if’ separation questions. The only remaining question – perhaps – is how best to structure a possible search through this list of fields?

Here’s the model we’ve been testing for the last few months. Although loathed to call it ’27-Windows’ that’s effectively what it is. The third dimension is all about ‘interfaces’ and we believe the three interface-related windows that need to be looked through and between are:

  • Intra – conditional field differences within elements of a system
  • Inter – conditional field differences between elements of a system
  • Extra – conditional field differences between elements within a system and those beyond it

Here’s what the 27-Windows might look like:

Figure 2: 27-Windows

If nothing else, early evidence of using the model tells us it satisfies the ‘comprehensive’ test. If you’re really looking for ‘the best’ solution to a problem, it’s the best way we’ve yet found to find it. The only problem – there’s always the ‘next contradiction’, right? – is that experience with just 9 windows tells us that people get bored long before they’ve reached the ninth one, so what chance they will make it all the way to 27?

Every contradiction, of course, has a solution. We just need to have a desire to solve it. If we end up with better solutions this time, we might bring some more discipline to the process next time.

Here’s an example: there’s a long-standing problem in the textile industry: textiles are soft and flexible, and so it’s very difficult for a robot to accurately and consistently sew different pieces together. That’s why whenever you see photos of a textile manufacture factory, it’s full of rows and rows of people guiding the pieces to be joined into the sewing machine. The textile industry looks like this because no-one has thought to try and solve the physical contradiction: we want the fabric to be stiff and flexible.

As soon as you allow yourself permission to contemplate solving this problem, it’s possible to find yourself a very simple separation in time opportunity as shown in Figure 3. Once you’ve found this, you’ve given yourself the opportunity to solve the problem by dipping the fabric in a (water-soluble) stiffener prior to sewing, and then washing the stiffener off again after the garment is sewn. On several levels, it’s a very nice solution. No more armies of seamsters and seamstresses; a few of them re-deployed to coating and washing stiffener into and out of the fabric. This is what the company, ‘Sewbo’ is proposing as their revolutionary solution to the industry. It’s a step change right enough, but, having given yourself permission to tackle the ‘stiff and flexible’ physical contradiction, was ‘separation in time’ the only or ‘best’ separation strategy to use?

Figure 3: Sewbo Physical Contradiction Separation-In Time Opportunity

Answer: I don’t think so.
I think there are several much more elegant solutions in some of the other windows. Your challenge for the month, is to look through one or two of them and see what you can come up with… the future of the global textile industry is in your hands. No pressure.