Monday, June 11, 2007

Pragmatism


If you would press me I would have to admit to being a pragmatic. It is, if you will, my preferred philosophy of science. Pragmatism in a nutshell simply says that if a theory is good at predicting the world as we perceive it and if it is useful in the sense that it allows us to create new technologies, then we will accept that theory and use it as if it was true.

Sometimes pragmatic theories are false even though they are pragmatic. Take Newtonian physics for example. Newton's laws can explain an almost limitless amount of experimental observations. The only problem is that it is false. Experiments which are designed so that one outcome would support Newton's theory and the other outcome Einstein's theory shows clearly that the latter set of laws provide you with the more accurate predictions. Yet, because they are so practical, we still use Newton's much less confusing laws for a lot of approximations. So in this case we say that because Newton's laws works really well for almost any calculations we don't care that they are not really true.

What then are we to make of the completely absurd and mind twisting theories of quantum physics, dark energy and the like? These theories, may I remind you, shape the foundation of most new technologies today, and the accuracy of predictions derived from quantum physics is equivalent to measuring the width of the United States with an error margin of about the width of a human hair!!! However, quantum physics also predicts that if there is a cat in a box (Schrödinger's cat, see above), it can be dead and alive at the same time!? To me this sounds like nonsense. I have certainly never seen a cat that is both dead and alive and if someone would say to me that they had seen such a cat I would feel obliged to call a mental institution. In my opinion, the only sensible conclusion is to say that, yes these are absurd theories, but they are indeed incredibly practical, so lets just use them as if they were true until we find something better (if we ever will that is).

I don't think that I am contradicting myself when I say that I also believe and care about what is true in an objective sense. Being a pragmatist, I think, is a progressive way of thinking. After all, if a theory was true in the objective sense then all predictions derived from that theory would also have to be true. To put it another way, the most practical theory of all would be the one that got it right…

I am personally hoping that some day a theory that I can understand and which does not make my head hurt, will come and replace quantum physics, dark energy and other similar theories. But for now I will accept these theories because of the fact that they are practical.

4 comments:

Z said...

... on my first quantum lesson i was stunned: Statistics AGAIN?
Didn't i just finish that course?

conclusion since that day:

Whenever human kind enters a new field, which needs an explanation and there is yet none (or explained in general but too complicated with lots of variables):
Tada.
We tend to use statistics.

And i think quantum level/ Planck level phenomena & some atom physics, is an evident case of this.
I will expand on this later

rasmussenanders said...

Does that mean that you think quantum physics follows causality and that we simply have not discovered the causes yet?

It is a good point the one you made about statistics.

z said...

yes,
empiric methods, like statistics, precede formulas and theories.

question is, how long will it take before we discover the causes, i mean, statistics itself can't be a cause (?).....

Or:
how long will it take before people like me realize that "quantum mechanics shows the truth"
i.e. whenever we see an outcome or result, we only see the most probable one....

Nice entry and cute cat photo

Z said...

But still working on the different suggestions of what the fotons are "knowing" and not knowing