“The Heaven of the Sun may be compared to Arithmetic on account of two properties; the first is, that with its light all the other stars are informed; the second is, that the eye cannot behold it. And these two properties are in Arithmetic, for with its light all the sciences are illuminated, since their subjects are all considered under some number, and in the consideration thereof we always proceed with numbers; as in natural science the subject is the movable body, which movable body has in it ratio of continuity, and this has in it ratio of infinite number. And the chief consideration of natural science is to consider the principles of natural things, which are three, namely, matter, species, and form; in which this number is visible, not only in all together, but, if we consider well, in each one separately.