More Than Fit For The Future An EvoDebate Position Statement Robert E. Smith Director The Intelligent Computer Systems Centre The University of The West of England, Bristol

Disheartening News: Empirical Demonstrations that show the region where EC is “best” amongst search algorithms is very narrow Criticisms of Holland’s Theories The No-Free-Lunch Theorem Leaving Us Asking: What is the niche for EC? Is it really that useful for anything? Have we all been deluded?

My Argument… Craft and Technology almost always lead scientific understanding Because of the hard edges of computing, computer scientists aren’t used to this fact Complex systems based paradigms (like EC) best lend themselves to craft

An Example Consider the longitude problem How does one determine one’s longitude on Earth? This was once the most important technical (and commercial) problem in the world Clocks (to determine one’s local time relative to home time) are provably inadequate for this task, since all clocks are always inaccurate

Clearly… The only solution for this task is an astronomical one, since time of day (and thus longitude) is an astronomical problem It was once accepted scientific fact that the only adequate solution for the longitude problem was to look up, at the perfect clockwork of the stars

The Real Solution

Harrison identified the problem… As technological, not scientific or mathematical. He asked: Could one make the inherently flawed clock good enough to solve the problem The fact that one could do so was a shock to the scientific world, but not to the world of craftsmen

Craft works beyond scientific understanding We in computing don’t usually face this fact

Another example Simon Newcomb (another astronomer) offered strong scientific arguments that heavier-than-air flight was impossible His chief arguments concerned scale up Weight scales as the cube, lift scales as the square, therefore, there is a limit to the size of heavier-than-air vehicles. Newcomb argued that large birds were clearly near this limit

And, of course, he was right Heavier-than-air flight has a very narrow space of usefulness 3/2 slope

No Free Lunch? No S*#t. Wolpert and Macready, 1995 When performance is averaged over all possible search spaces, all search algorithms perform equally well (including enumeration) This fact has nearly no practical value, and isn’t a surprise to technologists and engineers at all

So, I say: Delivering “pretty good” solutions is an important goal Concepts of crisp problems and crisp optimality are illusions that seldom exist in the real world Filling the pretty-good-solution niche is the appropriate goal for soft computing (particularly EC)

Suggested EC Concentrations co-evolution adaptive agents online adaptation to changing environments, machine innovation and creativity opening our minds to industrial problems where computer algorithms are yet to be applied, but where pretty-good, pretty-fast solutions have real cash value.