All this care for the world, we must believe, is taken by the Gods without any act of will or labour. As bodies which possess some power produce their effects by merely existing: e. g. the sun gives light and heat by merely existing; so, and far more so, the Providence of the Gods acts without effort to itself and for the good of the objects of its forethought. This solves the problems of the Epicureans, who argue that what is Divine neither has trouble itself nor gives trouble to others. The incorporeal providence of the Gods, both for bodies and for souls, is of this sort; but that which is of bodies and in bodies is different from this, and is called Fate, Heimarmenê, because the chain of causes (Heirmos) is more visible in the case of bodies; and it is for dealing with this Fate that the science of 'Mathematic' has been discovered.[211:1] Therefore, to believe that human things, especially their material constitution, are ordered not only by celestial beings but by the Celestial Bodies, is a reasonable and true belief. Reason shows that health and sickness, good fortune and bad fortune, arise according to our deserts from that source. But to attribute men's acts of injustice and lust to Fate, is to make ourselves good and the Gods bad. Unless by chance a man meant by such a statement that in general all things are for the good of the world and for those who are in a natural state, but that bad education or weakness of nature changes the goods of Fate for the worse. Just as it happens that the Sun, which is good for all, may be injurious to persons with ophthalmia or fever. Else why do the Massagetae eat their fathers, the Hebrews practise circumcision, and the Persians preserve rules of rank?[212:1] Why do astrologers, while calling Saturn and Mars 'malignant', proceed to make them good, attributing to them philosophy and royalty, generalships and treasures? And if they are going to talk of triangles and squares, it is absurd that gods should change their natures according to their position in space, while human virtue remains the same everywhere. Also the fact that the stars predict high or low rank for the father of the person whose horoscope is taken, teaches that they do not always make things happen but sometimes only indicate things. For how could things which preceded the birth depend upon the birth? Further, as there is Providence and Fate concerned with nations and cities, and also concerned with each individual, so there is also Fortune, which should next be treated. That power of the gods which orders for the good things which are not uniform, and which happen contrary to expectation, is commonly called Fortune, and it is for this reason that the goddess is especially worshipped in public by cities; for every city consists of elements which are not uniform. Fortune has power beneath the moon, since above the moon no single thing can happen by fortune.