A statement of the type 'All men are mortal; Socrates is a man; therefore Socrates is mortal' does not constitute a prediction but the deduction of a self-evident truth. To say that an exhaustible resource will be exhausted is not a prediction but, under certain conditions, a tautology. The only qualification is that an exhaustible resource will not be exhausted if , for some reason, production ceases while reserves are still available. The statement that the production of crude oil, an

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... ble resource, will reach a peak will not be entirely a tautology if it also told us something about the production pattern over time; something that is not necessarily implied in the exhaustibility concept. The peak story tells us, indeed, that after rising over years, decades or centuries, production will enter a phase of decline. The peak could take different shapes however. It could appear as the apex of an acute angle, or stretch out over a long period in the form of a plateau, or emerge more than once in the shape of a saddle or as a chain of dunes. In short, it is not sufficient to say that an exhaustible resource will be eventually exhausted and that its production will decline until extinction after reaching a peak. These are not predictions. Such statements are of no interest whatsoever unless we are told the dates at which the peak will be reached, and the likely shape of the production curve before and after the peak.