In the language of the New Platonists, the number seven is said to be a virgin, and without a mother, and it is therefore sacred to w:MinervaMinerva. The number six is a perfect number, and is consecrated to Venus. The relations of space were dealt with...

in: I. The Greek school philosophy, with reference to physical science. II. The physical sciences in ancient Greece. III. Greek astronomy. IV. Physical science in the middle ages. V. Formal astronomy after the stationary period. VI. Mechanics, including fluid mechanics. VII. Physical astronomy. Additions to the 3d ed, D. Appleton, 1874, p. 217