But things which are contracted contrary to nature are by nature at war, and force themselves apart; and to this war and convulsion the name of shivering and trembling is given; and the whole affection and the cause of the affection are both termed cold. That is called hard to which our flesh yields, and soft which yields to our flesh; and things are also termed hard and soft relatively to one another. That which yields has a small base; but that which rests on quadrangular bases is firmly posed and belongs to the class which offers the greatest resistance; so too does that which is the most compact and therefore most repellent. The nature of the light and the heavy will be best understood when examined in connexion with our notions of above and below; for it is quite a mistake to suppose that the universe is parted into two regions, separate from and opposite to each other, the one a lower to which all things tend which have any bulk, and an upper to which things only ascend against their will. For as the universe is in the form of a sphere, all the extremities, being equidistant from the centre, are equally extremities, and the centre, which is equidistant from them, is equally to be regarded as the opposite of them all. Such being the nature of the world, when a person says that any of these points is above or below, may he not be justly charged with using an improper expression? For the centre of the world cannot be rightly called either above or below, but is the centre and nothing else; and the circumference is not the centre, and has in no one part of itself a different relation to the centre from what it has in any of the opposite parts. Indeed, when it is in every direction similar, how can one rightly give to it names which imply opposition? For if there were any solid body in equipoise at the centre of the universe, there would be nothing to draw it to this extreme rather than to that, for they are all perfectly similar; and if a person were to go round the world in a circle, he would often, when standing at the antipodes of his former position, speak of the same point as above and below; for, as I was saying just now, to speak of the whole which is in the form of a globe as having one part above and another below is not like a sensible man.

τὸ δὲ παρὰ φύσιν συναγόμενον μάχεται κατὰ φύσιν αὐτὸ ἑαυτὸ εἰς τοὐναντίον ἀπωθοῦν. τῇ δὴ μάχῃ καὶ τῷ σεισμῷ τούτῳ τρόμος καὶ ῥῖγος ἐτέθη͵ ψυχρόν τε τὸ πάθος ἅπαν τοῦτο καὶ τὸ δρῶν αὐτὸ ἔσχεν ὄνομα. σκληρὸν δέ͵ ὅσοις ἂν ἡμῶν ἡ σὰρξ ὑπείκῃ͵ μαλακὸν δέ͵ ὅσα ἂν τῇ σαρκί· πρὸς ἄλληλά τε οὕτως. ὑπείκει δὲ ὅσον ἐπὶ σμικροῦ βαίνει· [62c] τὸ δὲ ἐκ τετραγώνων ὂν βάσεων͵ ἅτε βεβηκὸς σφόδρα͵ ἀντιτυπώτατον εἶδος͵ ὅτι τε ἂν εἰς πυκνότητα συνιὸν πλείστην ἀντίτονον ᾖ μάλιστα. βαρὺ δὲ καὶ κοῦφον μετὰ τῆς τοῦ κάτω φύσεως ἄνω τε λεγομένης ἐξεταζόμενον ἂν δηλωθείη σαφέστατα. φύσει γὰρ δή τινας τόπους δύο εἶναι διειληφότας διχῇ τὸ πᾶν ἐναντίους͵ τὸν μὲν κάτω͵ πρὸς ὃν φέρεται πάνθ΄ ὅσα τινὰ ὄγκον σώματος ἔχει͵ τὸν δὲ ἄνω͵ πρὸς ὃν ἀκουσίως ἔρχεται πᾶν͵ οὐκ ὀρθὸν οὐδαμῇ νομίζειν· [62d] τοῦ γὰρ παντὸς οὐρανοῦ σφαιροειδοῦς ὄντος͵ ὅσα μὲν ἀφεστῶτα ἴσον τοῦ μέσου γέγονεν ἔσχατα͵ ὁμοίως αὐτὰ χρὴ ἔσχατα πεφυκέναι͵ τὸ δὲ μέσον τὰ αὐτὰ μέτρα τῶν ἐσχάτων ἀφεστηκὸς ἐν τῷ καταντικρὺ νομίζειν δεῖ πάντων εἶναι. τοῦ δὴ κόσμου ταύτῃ πεφυκότος͵ τί τῶν εἰρημένων ἄνω τις ἢ κάτω τιθέμενος οὐκ ἐν δίκῃ δόξει τὸ μηδὲν προσῆκον ὄνομα λέγειν; ὁ μὲν γὰρ μέσος ἐν αὐτῷ τόπος οὔτε κάτω πεφυκὼς οὔτε ἄνω λέγεσθαι δίκαιος͵ ἀλλ΄ αὐτὸ ἐν μέσῳ· ὁ δὲ πέριξ οὔτε δὴ μέσος οὔτ΄ ἔχων διάφορον αὑτοῦ μέρος ἕτερον θατέρου μᾶλλον πρὸς τὸ μέσον ἤ τι τῶν καταντικρύ. τοῦ δὲ ὁμοίως πάντῃ πεφυκότος ποῖά τις ἐπιφέρων ὀνόματα αὐτῷ ἐναντία καὶ πῇ καλῶς ἂν ἡγοῖτο λέγειν; [63a] εἰ γάρ τι καὶ στερεὸν εἴη κατὰ μέσον τοῦ παντὸς ἰσοπαλές͵ εἰς οὐδὲν ἄν ποτε τῶν ἐσχάτων ἐνεχθείη διὰ τὴν πάντῃ ὁμοιότητα αὐτῶν· ἀλλ΄ εἰ καὶ περὶ αὐτὸ πορεύοιτό τις ἐν κύκλῳ͵ πολλάκις ἂν στὰς ἀντίπους ταὐτὸν αὐτοῦ κάτω καὶ ἄνω προσείποι. τὸ μὲν γὰρ ὅλον͵ καθάπερ εἴρηται νυνδή͵ σφαιροειδὲς ὄν͵ τόπον τινὰ κάτω͵ τὸν δὲ ἄνω λέγειν ἔχειν οὐκ ἔμφρονος·