§2.7#1Οὗ μὲν οὖν ἐστιν ἡ ὄψις, τοῦτʼ ἐστὶν ὁρατόν.
That of which there is sight, then, is the visible.
ὁρατὸν δʼ ἐστὶ χρῶμά τε καὶ ὃ λόγῳ μὲν ἔστιν εἰπεῖν, ἀνώνυμον δὲ τυγχάνει ὄν·
And the visible is both color and that which can be described in words but happens to have no name.
δῆλον δὲ ἔσται ὃ λέγομεν προελθοῦσι.
What we mean will become clear as we proceed.
τὸ γὰρ ὁρατόν ἐστι χρῶμα, τοῦτο δʼ ἐστὶ τὸ ἐπὶ τοῦ καθʼ αὑτὸ ὁρατοῦ· καθʼ αὑτὸ δὲ οὐ τῷ λόγῳ, ἀλλʼ ὅτι ἐν ἑαυτῷ ἔχει τὸ αἴτιον τοῦ εἶναι ὁρατόν.
For the visible is color, and this is that which is on the visible in itself; "in itself" not by definition, but because it has in itself the cause of its being visible.
πᾶν δὲ χρῶμα κινητικόν ἐστι τοῦ κατ᾿ ἐνέργειαν διαφανοῦς, καὶ τοῦτʼ ἐστὶν αὐτοῦ ἡ φύσις.
Every color is capable of setting in motion that which is actually transparent, and this is its nature.
διόπερ οὐχ ὁρατὸν ἄνευ φωτός, ἀλλὰ πᾶν τὸ ἑκάστου χρῶμα ἐν φωτὶ ὁρᾶται.
Therefore it is not visible without light, but every color of each thing is seen in light.
διὸ περὶ φωτὸς πρῶτον λεκτέον τί ἐστιν.
Wherefore we must first say what light is.
ἔστι δή τι διαφανές.
There is, then, something transparent.
διαφανὲς δὲ λέγω ὃ ἔστι μὲν ὁρατόν, οὐ καθʼ αὑτὸ δὲ ὁρατὸν ὡς ἁπλῶς εἰπεῖν, ἀλλὰ διʼ ἀλλότριον χρῶμα.
And I call "transparent" that which is visible, indeed, yet not visible in itself, to speak simply, but through an extraneous color.
τοιοῦτον δέ ἐστιν ἀὴρ καὶ ὕδωρ καὶ πολλὰ τῶν στερεῶν· οὐ γὰρ ὕδωρ οὐδʼ ἀήρ, διαφανές, ἀλλʼ ὅτι ἔστι τις φύσις ἐνυπάρχουσα ἡ αὐτὴ ἐν τούτοις ἀμφοτέροις καὶ ἐν τῷ ἀϊδίῳ τῷ ἄνω σώματι.
And of this sort are air and water and many of the solids; for it is not qua water or air that they are transparent, but because there is a certain nature inherent in both of them, and in the eternal body above.
φῶς δέ ἐστιν ἡ τούτου ἐνέργεια, τοῦ διαφανοῦς ᾖ διαφανές.
And light is the activity of this, of the transparent qua transparent.
δυνάμει δέ, ἐν ᾧ τοῦτʼ ἐστί, καὶ τὸ σκότος.
And potentially, in which this is, there is also darkness.
τὸ δὲ φῶς οἷον χρῶμά ἐστι τοῦ διαφανοῦς, ὅταν ᾗ ἐντελεχείᾳ διαφανὲς ὑπὸ πυρὸς ἢ τοιούτου οἷον τὸ ἄνω σῶμα· καὶ γὰρ τούτῳ τι ὑπάρχει ἓν καὶ ταὐτόν.
And light is like a color of the transparent, when it is actually transparent through fire or something such as the upper body; for to this too there belongs something one and the same.
τί μὲν οὖν τὸ διαφανὲς καὶ τί τὸ φῶς, εἴρηται, ὅτι οὔτε πῦρ οὔθʼ ὅλως σῶμα οὐδʼ ἀπορροὴ σώματος οὐδενός (εἴη γὰρ ἂν σῶμά τι καὶ οὕτως), ἀλλὰ πυρὸς ἢ τοιούτου τινός παρουσία ἐν τῷ διαφανεῖ· οὔτε γὰρ δύο σώματα ἅμα δυνατὸν ἐν τῷ αὐτῷ εἶναι, δοκεῖ τε τὸ φῶς ἐναντίον εἶναι τῷ σκότει· ἔστι δὲ τὸ σκότος στέρησις τῆς τοιαύτης ἕξεως ἐκ διαφανοῦς, ὥστε δῆλον ὅτι καὶ ἡ τούτου παρουσία τὸ φῶς ἐστιν.
What the transparent is, then, and what light is, has been stated, namely that it is neither fire nor generally a body, nor an efflux of any body (for then it would be a certain body in that case too), but the presence of fire or some such thing in the transparent; for it is not possible for two bodies to be in the same place at the same time, and light seems to be the contrary of darkness; and darkness is the privation of such a state from the transparent, so that it is clear that the presence of this is light.
καὶ οὐκ ὀρθῶς Ἐμπεδοκλῆς, οὐδʼ εἴ τις ἄλλος οὕτως εἴρηκεν, ὡς φερομένου τοῦ φωτὸς καὶ τεινομένου ποτὲ μεταξὺ τῆς γῆς καὶ τοῦ περιέχοντος, ἡμᾶς δὲ λανθάνοντος· τοῦτο γάρ ἐστι καὶ παρὰ τὴν τοῦ λόγου ἐνάργειαν καὶ παρὰ τὰ φαινόμενα· ἐν μικρῷ μὲν γὰρ διαστήματι λάθοι ἄν, ἀπʼ ἀνατολῆς δʼ ἐπὶ δυσμὰς τὸ λανθάνειν μέγα λίαν τὸ αἴτημα.
And Empedocles was not right, nor if anyone else has spoken thus, in saying that light travels and is at some time extended between the earth and that which surrounds it, though it escapes our notice; for this is both contrary to the clarity of reason and contrary to appearances; for in a small distance it might escape notice, but that it should escape notice from the east to the west is too great an assumption.
ἔστι δὲ χρώματος μὲν δεκτικὸν τὸ ἄχρουν, ψόφου δὲ τὸ ἄψοφον.
Now, that which is colorless is receptive of color, and the soundless of sound.
ἄχρουν δʼ ἐστὶ τὸ διαφανὲς καὶ τὸ ἀόρατον ἢ τὸ μόλις ὁρώμενον, οἶον δοκεῖ τὸ σκοτεινόν.
And the colorless is the transparent and the invisible, or that which is scarcely seen, such as the dark seems to be.
τοιοῦτον δὲ τὸ διαφανὲς μέν, ἀλλʼ οὐχ ὅταν ᾗ ἐντελεχείᾳ διαφανές, ἀλλʼ ὅταν δυνάμει· ἡ γὰρ αὐτὴ φύσις ὁτὲ μὲν σκότος ὁτὲ δὲ φῶς ἐστίν.
And the transparent is of this sort, but not when it is actually transparent, but when potentially so; for the same nature is at one time darkness and at another time light.