" The same thing happens in the search for the laws of historical movement.
The movement of mankind, proceeding from a countless number of human wills, occurs continuously.
To comprehend the laws of this movement is the goal of history. But in order to comprehend the laws of the continuous movement of the sum of all individual wills, human reason allows for arbitrary, discrete units. The first method of history consists in taking an arbitrary series of continuous events and examining it separately from others, whereas there is not and cannot be a beginning to any event, but one event always continuously follows another. The second method consists in examining the actions of one person, a king, a commander, as the sum of individual wills, whereas the sum of individual wills is never expressed in the activity of one historical person.
Historical science in its movement always takes ever smaller units for examination, and in this way strives to approach the truth. But however small the units that history takes, we feel that allowing for a unit that is separate from another, allowing for the beginning of some phenomenon, and allowing for the notion that all individual wills are expressed in the actions of one historical person, is false in itself.
Any conclusion of historical science, without the least effort on the part of criticism, falls apart like dust, leaving nothing behind, only as a result of the fact that criticism selects as an object for observation a larger or smaller discrete unit, which it always has the right to do, because any chosen historical unit is always arbitrary.
Only by admitting an infinitesimal unit for observation—a differential of history, that is, the uniform strivings of people—and attaining to the art of intigrating them (taking the sums of these infinitesimal quantities) can we hope to comprehend the laws of history. "

― Leo Tolstoy , War and Peace