The other factor is determined by a progression; it is still something linear, but its determinateness as magnitude is more complex; in so far as it can be expressed by a series, the task of summing it is called analytical, that is, arithmetical; but the geometrical moment in it is the multiplication, and this is the qualitative moment of transition from the dimension of line to that of plane; the one factor has been taken as discrete only for the arithmetical determination of the other; by itself, like the other, it is the magnitude of something linear.