Spinoza's Definition of Circle

Spinoza defines Circle as 'the figure described by the movement of a line, in which one end is fixed and the other is free'. In other words, he defines Circle in terms of Straight Line and Point. However, the difficulty with the definition is the meaning of 'fixed', for, if it means 'immobile', then not only one end, but the whole line is immobilized if that one end is. In actuality, what he is referring to as 'fixed' is a pivoting on one end, as the use of a compass to draw a circle demonstrates. But to 'pivot' means to 'rotate', the understanding of which presupposes that of the concept of Circularity. Hence, Spinoza's definition not only does not refute the hypothesis previously proposed here--that the Center of a Circle is itself a Circle, i. e. a relatively smaller one--it tends to support it.