Lives and Opinions of Eminent Philosophers

"The size of the sun and the other heavenly bodies, with respect to us, is just as great as it appears; [this is also in the eleventh book On Nature; for he says, 'if it had lost its size on account of distance, it would much more have lost its color; for there is no other distance more proportionate to this than that.'] But with respect to itself, it happens to be either greater than what is seen, or slightly smaller, or of the same size. For in this way fires among us too, when viewed from a distance, are viewed according to perception. And any objection on this point will be easily dissolved if one attends to evident perceptions, as we demonstrate in the books On Nature.

"The risings and settings of the sun, moon, and the other heavenly bodies can occur both by ignition and extinction, circumstances being such in each of the two regions that the aforementioned results are accomplished; for none of the phenomena bears contrary witness. And the aforementioned could also be brought about by appearance above the earth and again by occlusion; for not any of the phenomena bears contrary witness. Nor is it impossible that their motions take place in accordance with the rotation of the whole heaven, or while the latter is at rest, by the rotation of the bodies themselves, generated from the beginning in the birth of the world by necessity in the east;

​... by the most intense heat, according to a certain grazing spread of fire advancing always to adjacent places. "The turnings of the sun and moon admit of coming to be by the obliquity of heaven, constrained in this way by the seasons; likewise also by the counter-pressure of air, or even by appropriate fuel, as the adjacent material is always ignited while what is spent fails; or even because from the beginning such a rotation was wrapped into these heavenly bodies so as to move in a kind of spiral. For all such explanations and those akin to them are in disagreement with none of the evident perceptions, if one always holds fast to the possible in such matters and is able to bring each of these into harmony with the phenomena, not fearing the slavish contrivances of the astrologers.

"The waning of the moon and its waxing again could occur both by the rotation of this body and likewise by the formations of air, and furthermore by obstructions and in all the ways in which the phenomena among us also invite explanations of this kind—provided one has not become enamored of the single method and empty-mindedly rejected the others, having failed to observe what is possible for a human being to observe and what is impossible, and on this account desiring to observe impossibilities. Furthermore, it is possible for the moon to have its light from itself, and it is possible to have it from the sun.

​For among us too many things are observed to possess light from themselves, and many from other things. And none of the phenomena in the heavens stands as an obstacle, if one always holds in memory the multiple method and contemplates together with them the attendant hypotheses and causes, and does not, by gazing toward what is inconsistent, vainly puff these matters up and incline now this way, now that toward the single method. The appearance of the face in it can occur both by the variation of parts and by occlusion, and by whatever ways might be observed that possess harmony with the phenomena.

​For in the case of all celestial phenomena such tracking must not be abandoned; for if one fights against evident perceptions, he will never be able to partake of genuine tranquility. "An eclipse of the sun and moon can occur both by extinction, just as this is observed to happen among us, and also already by the occlusion of certain other bodies, either of the earth or of some other invisible entity of this kind. And in this manner one must contemplate together the methods akin to one another, and that the simultaneous coincidences of certain occurrences are not impossible. [And in the twelfth book On Nature he says these things, and in addition that the sun is eclipsed when the moon casts a shadow, and the moon by the shadow of the earth, but also by retreat.]