Geology as a Science

Why is it so difficult to predict earthquakes?

Ingenious scientists have been studying the matter for a long time, there is a wonderful incentive for success in this endeavor -- since many lives as well as a lot of property are threatened by the continued randomness of these planetary upheavals -- and the basic theory of plate tectonics seems to have been worked out in elaborate detail. So ... why no predictions?

Here's a column on the general point by Robert Roy Britt, managing editor of LiveScience.

But what Britt doesn't mention is the intriguing fact that geology is a science with a sample size of one. In the study of human physiology and its disorders, we can treat any human who has ever been subjected to medical study as a separate sample. From all of these samples, the relevant research community can draw important generalizations. In the study of the internal workings of the earth and what (from our puny point of view as its surface dwellers) we may call its "disorders," though, we have only the one Earth. Our knowledge of other planets is rudimentary, our knowledge of their internal workings is, I suspect, nil.

We have many observations of the earth and different earthquakes, but the multiplicity of observations doesn't make for a large sample. You can take my temperature several times, if you like. Each of those readings will be a fact about a single organism, reflecting either its equilibrium or some change in its condition over the period in which your measurements were take. There is still just the one organism.

This line of thought could lead us in any of several directions, most of them moving far beyond the quotidian difficulty in predicting earthquakes with which we began. It could lead us into metaphysics, for example, and the question of what constitutes a "thing," an "entity," even if you like a "substantial form." That is on some readings THE problem of metaphysics. But I'll leave off here for the day.