Both history of nature and history of humanity are 'historical' and yet cannot dispense with uniformity. In both there is 'uniformity' ('science') as well as non-uniformity ('history'); in both 'history respects itself and 'history does not repeat itself. But, as even the history of humanity has its uniformitarian features, uniformity can still less be dispensed with in 'history' of nature, which, being one of the natural sciences, is less historical and, consequently, more uniformitarian.

The history of science shows so many examples of the 'irrational' notions and theories of to-day becoming the 'rational' notions and theories of to-morrow, that it seems largely a matter of being accustomed to them whether they are considered rational or not, natural or not.

The student of palaetiological sciences is a scientist and a historian. The former tries to be as uniformitarian as possible, the latter has to recognize the contingency of events which will ever be a 'skandalon' to the scientist. Verily, the geologist 'lives in a divided world'.