[Peter Cariani, 960314, 1200]

Bill Powers 3/13/96 wrote:

When you apply a force to a mass, you get an acceleration. We represent

this relationship as f = ma. But what is it that makes the mass

accelerate when the force is applied? It is not the algorithm, f = ma.

The symbols f, m, and a stand for measurements -- i.e., perceptions. The

perceptions are not what create the behavior. In fact, even f, m, and a

are themselves perceptual representations of some external sea of

variables and interactions which can't possibly be as simple as the

symbols that we use to speak about them. What f=ma does is to _impose

order_ on our experiences. It simplifies our interactions with the

external world, making them comprehensible. But our symbolic

representations of the world no more make it work than the words "200-

horsepower engine" make a car run.

Yes. I think the symbols that we use allow us to order our perceptions in

such a way so as to permit us to carry out a reliable sequence of

behaviors (symbol manipulations). So mathematical operations are a

means by which we can reliably replicate sequences of behaviors to

achieve consistent ends, across repetitions and observers. These

behaviors are all contingent upon our previous perceptions and

vice-versa --the use of discrete symbols makes these looping sequences

extremely reliable.

I think of mathematical notations and operations as one means

of externalizing chains of thoughts so as to make them more reliable.

When they are sufficiently reliable and explicit to permit

many different observer-participants to replicate our results

without (apparent) ambiguity or error, then I am willing to call them

"computations" and "algorithms".

And yes, simulated fires do not burn us. Aristotle made similar

criticisms of Pythagorean theories of the motions of planets.

Pattee and I tried over and over to convey the distinction

between symbolic representations and material

process to the Alife community, but with only limited success.

Peter Cariani