על החלומות, ספר א ד׳On Dreams, Book I 4

א׳
1[21] All these we perceive; but heaven has sent to us no sure indication of its nature, but keeps it beyond our comprehension.  For what can we say? That it is a fixed mass of crystal, as some have thought? Or that it is absolutely pure fire? Or that it is a fifth substance, circular in movement, with no part in the four elements? Again, we ask, has the fixed and outmost sphere upward-reaching depth, or is it nothing but a superficies, without depth, resembling plane geometrical figures?
ב׳
2[22] Again: are the stars lumps of earth full of fire? Some people have declared them to be dells and glades and masses of fiery metal, for which they themselves deserve a prison and mill-house, in which such instruments are kept to punish impiety.  Or are the stars an unbroken, and, as one has said, “close” harmony, indissoluble compresses of ether? Are they living and intelligent, or devoid of intelligence and conscious life? Are their motions determined by choice or simply by necessity?
ג׳
3[23] Does the moon contribute a light of its own or a borrowed light caused by the rays of the sun shining on it? Or is it neither the one nor the other by itself absolutely, but the combined result of both, a mixture such as we might expect from a fire partly its own, partly borrowed? Yes, all these and suchlike points pertaining to heaven, that fourth and best cosmic substance, are obscure and beyond our apprehension, based on guess-work and conjecture, not on the solid reasoning of truth;
ד׳
4[24] so much so that one may confidently take one’s oath that the day will never come when any mortal shall be competent to arrive at a clear solution of any of these problems. This is why the fourth and waterless well was named “Oath,” being the endless and altogether baffling quest of the fourth cosmic region, heaven.