Saturday, October 10, 2009

Lean versus Complex

Some interesting discussion contrasting Lean with Complex Adaptive Systems (CAS).

The Danger of Complex Adaptive Systems (Alan Shalloway)
The Danger of Lean - Ignoring Social Complexity (Jurgen Appelo)

Alan has a nice example of a school of mullet being consumed by a gang of dolphins. The mullet (species) has evolved a stratagem of swimming together to protect against predators. The dolphins (species) have evolved a higher intelligence, which enables them (specific individuals) to exploit the stratagem for their own advantage.

Which is the complex adaptive system here? Alan thinks it is the mullet system, and questions the value of CAS for protecting the mullet against risk. It is true that the mullet system has a degree of complexity: the dolphin cannot predict the path of a single fish, and can only nudge the system rather than control it exactly. But the mullet system is up against a much more intelligent adaptive system - that of the dolphins, whose tactics are learned rather than inherited.

Inherited behaviour, however complex it may seem, represents an adaptation to past challenges. Sometimes the same can be true of learned behaviour - the habits of management and problem-solving that have worked in the past. But in a dynamic competitive environment, the advantage of learned behaviour is that it can be changed. We regard dolphins as more intelligent than mullet because they are able to learn new behaviours, both by themselves and from one another.

Jurgen explains the problem of Lean and the advantage of CAS in terms of Cynefin. Appealing to a simplistic distinction drawn by Dave Snowden between "systems thinking" and "social complexity", he labels Lean as "systems thinking", argues that Lean fails to handle social complexity, and dismisses (that school of) systems thinking as outdated.

I prefer to explain the problem of Lean using ideas borrowed from Bateson. Lean is an adaptation that makes predictable systems more efficient. But highly adapted systems typically lack future adaptability. The mullet strategy is vulnerable to the dolphin intelligence. Indeed, the dolphin intelligence has evolved, among other things, in order to overcome the mullet strategy. So which system is the more complex, which system is the more adaptive?


Alan has withdrawn his post rather than continue the argument with Jurgen. There is an archive version of the post on the Wayback Machine, complete with an interesting discussion thread.

Updated 2 December 2016


  1. Until either mullets or dolphins (or whatever they evolve into) are extinct I find it hard compare how good or succesful the two species (and their "strategies")are...

  2. I agree with a jangbrand. Both species are successful complex adaptive systems, as evidenced by the fact that neither is extinct.

    Dolphins may be more "intelligent" as individuals but the mullet compensate by acting in unison, producing an emergent defensive phenomenon (the school) that is "larger" than any single dolphin. Sure, a dolphin is more likely to nab a meal this way, but the mullet system remains intact. Neither system wins, neither system loses, but individuals from both live on to reproduce.

    Consider ants and humans--one seemingly advantaged by intelligence, the other seemingly disadvantaged by simplicity. But ants, because of their social loyalty, are arguably more successful as a species than humans. (Ants inhabit more of the planet than humans do.) The fact that I can bag an ant anytime I want doesn't make humans any more evolved or complex.

  3. Of course the mullet school is larger than any single dolphin. The dolphin operate in gangs, so that they can eat the entire school between them.

    Marc says that the mullet system remains intact. I guess that's half-true, at least until the mullet are driven extinct by over-greedy dolphin. ("So long, and thanks for all the fish.") Perhaps only then will Anders be willing to make a judgement on how successful the two species were.

    But I wasn't claiming that dolphin were more successful, or that they would survive longer as a species, merely that they manifested a different degree of adaptation. Obviously it would be false anthropomorphism to suppose that the dolphin are superior because they are more like ourselves.

  4. @ Richard Veryard "So which system is the more complex, which system is the more adaptive?"
    Neither alone: mullets + dolphins = CAS

    1. In the debate between Alan and Jurgen, the mullet and the dolphins are each described as (complex) systems. Neither of them look at the mullet-dolphin system, which as Yves points out, is equally interesting in terms of adaptation. Or as Bateson puts it, "survival of the fit". See Dennis Leri, Darwinian Evolution (1997)