Aristotle · Metaphysics §4.5#2
Refutation of Universal Flux and Objective Basis of Sensation
Summary
Aristotle criticizes the extreme skepticism of Cratylus and others that arises from the doctrine of universal flux, distinguishing between change in quantity and the constancy of form, and pointing to the immobility of the heavenly bodies. He further argues against those who relativize perception, showing that the underlying external substance causing sensation must exist prior to the sensation itself.
§4.5#2ἐν δὲ τούτοις πολλὴ ἡ τοῦ ἀορίστου φύσις ἐνυπάρχει καὶ ἡ τοῦ ὄντος οὕτως ὥσπερ εἴπομεν·
But in these opinions there is present much of the nature of the indeterminate, and of being in the way we have said.
διὸ εἰκότως μὲν λέγουσιν, οὐκ ἀληθῆ δὲ λέγουσιν (οὕτω γὰρ ἁρμόττει μᾶλλον εἰπεῖν ἢ ὥσπερ Ἐπίχαρμος εἰς Ξενοφάνην).
Therefore, they speak reasonably, but they do not speak truly (for it is more fitting to put it this way than as Epicharmus did against Xenophanes).
ἔτι δὲ πᾶσαν ὁρῶντες ταύτην κινουμένην τὴν φύσιν, κατὰ δὲ τοῦ μεταβάλλοντος οὐθὲν ἀληθευόμενον, περί γε τὸ πάντῃ πάντως μεταβάλλον οὐκ ἐνδέχεσθαι ἀληθεύειν.
Furthermore, seeing all this nature in motion, and that nothing is asserted truly of that which is changing, they concluded that about that which is changing in every way and in every respect it is impossible to speak truly.
ἐκ γὰρ ταύτης τῆς ὑπολήψεως ἐξήνθησεν ἡ ἀκροτάτη δόξα τῶν εἰρημένων, ἡ τῶν φασκόντων ἡρακλειτίζειν καὶ οἵαν Κρατύλος εἶχεν, ὃς τὸ τελευταῖον οὐθὲν ᾤετο δεῖν λέγειν ἀλλὰ τὸν δάκτυλον ἐκίνει μόνον, καὶ Ἡρακλείτῳ ἐπετίμα εἰπόντι ὅτι δὶς τῷ αὐτῷ ποταμῷ οὐκ ἔστιν ἐμβῆναι· αὐτὸς γὰρ ᾤετο οὐδʼ ἅπαξ.
For from this supposition blossomed the most extreme of the mentioned opinions, namely that of those who claim to follow Heraclitus, and such as Cratylus held, who in the end thought that one ought to say nothing but only moved his finger, and censured Heraclitus for saying that it is not possible to step twice into the same river; for he himself thought not even once.
ἡμεῖς δὲ καὶ πρὸς τοῦτον τὸν λόγον ἐροῦμεν ὅτι τὸ μὲν μεταβάλλον ὅτε μεταβάλλει ἔχει τινὰ αὐτοῖς λόγον μὴ οἴεσθαι εἶναι, καίτοι ἔστι γε ἀμφισβητήσιμον· τό τε γὰρ ἀποβάλλον ἔχει τι τοῦ ἀποβαλλομένου, καὶ τοῦ γιγνομένου ἤδη ἀνάγκη τι εἶναι, ὅλως τε εἰ φθείρεται, ὑπάρξει τι ὄν, καὶ εἰ γίγνεται, ἐξ οὗ γίγνεται καὶ ὑφʼ οὗ γεννᾶται ἀναγκαῖον εἶναι, καὶ τοῦτο μὴ ἰέναι εἰς ἄπειρον.
But we shall say against this argument too that, while that which is changing, when it changes, gives them some reason to think that it does not exist, yet this is at least disputable; for that which is losing something still has something of that which is being lost, and of that which is coming to be, something must already exist; and on the whole, if it is being destroyed, there will exist something that is, and if it is coming to be, that from which it comes to be and that by which it is generated must exist, and this cannot go on to infinity.
ἀλλὰ ταῦτα παρέντες ἐκεῖνα λέγωμεν, ὅτι οὐ ταὐτό ἐστι τὸ μεταβάλλειν κατὰ τὸ ποσὸν καὶ κατὰ τὸ ποιόν· κατὰ μὲν οὖν τὸ ποσὸν ἔστω μὴ μένον, ἀλλὰ κατὰ τὸ εἶδος ἅπαντα γιγνώσκομεν.
But leaving these things aside, let us say this: that to change in quantity is not the same as to change in quality; let it be, then, that in quantity a thing does not remain, but we know all things according to their form.
ἔτι δʼ ἄξιον ἐπιτιμῆσαι τοῖς οὕτως ὑπολαμβάνουσιν, ὅτι καὶ αὐτῶν τῶν αἰσθητῶν ἐπὶ τῶν ἐλαττόνων τὸν ἀριθμὸν ἰδόντες οὕτως ἔχοντα περὶ ὅλου τοῦ οὐρανοῦ ὁμοίως ἀπεφήναντο· ὁ γὰρ περὶ ἡμᾶς τοῦ αἰσθητοῦ τόπος ἐν φθορᾷ καὶ γενέσει διατελεῖ μόνος ὤν, ἀλλʼ οὗτος οὐθὲν ὡς εἰπεῖν μόριον τοῦ παντός ἐστιν, ὥστε δικαιότερον ἂν διʼ ἐκεῖνα τούτων ἀπεψηφίσαντο ἢ διὰ ταῦτα ἐκείνων κατεψηφίσαντο.
Furthermore, it is worthy of censure in those who hold this opinion that, although they saw that this is the case only among the smaller number of sensible things, they declared in like manner about the whole heaven; for the region of the sensible around us alone is continually in destruction and generation, but this is, so to speak, no fraction of the whole, so that it would have been more just to acquit these because of those, rather than to condemn those because of these.
ἔτι δὲ δῆλον ὅτι καὶ πρὸς τούτους ταὐτὰ τοῖς πάλαι λεχθεῖσιν ἐροῦμεν· ὅτι γὰρ ἔστιν ἀκίνητός τις φύσις δεικτέον αὐτοῖς καὶ πειστέον αὐτούς.
Furthermore, it is clear that against these too we shall say the same things as were said before; for that there is some immovable nature must be shown to them, and they must be convinced of it.
καίτοι γε συμβαίνει τοῖς ἅμα φάσκουσιν εἶναι καὶ μὴ εἶναι ἠρεμεῖν μᾶλλον φάναι πάντα ἢ κινεῖσθαι· οὐ γὰρ ἔστιν εἰς ὅ τι μεταβαλεῖ· ἅπαντα γὰρ ὑπάρχει πᾶσιν.
And yet, it happens to those who say at the same time that a thing is and is not, that they must say all things are at rest rather than in motion; for there is nothing into which they can change, for all things are already present in all.
—περὶ δὲ τῆς ἀληθείας, ὡς οὐ πᾶν τὸ φαινόμενον ἀληθές, πρῶτον μὲν ὅτι οὐδʼ εἰ ἡ αἴσθησις μὴ ψευδὴς τοῦ γε ἰδίου ἐστίν, ἀλλʼ ἡ φαντασία οὐ ταὐτὸν τῇ αἰσθήσει.
And concerning truth, to show that not every appearance is true, first of all, even if sensation is not false concerning its own proper object, yet imagination is not the same as sensation.
εἶτʼ ἄξιον θαυμάσαι εἰ τοῦτʼ ἀποροῦσι, πότερον τηλικαῦτά ἐστι τὰ μεγέθη καὶ τὰ χρώματα τοιαῦτα οἷα τοῖς ἄπωθεν φαίνεται ἢ οἷα τοῖς ἐγγύθεν, καὶ πότερον οἷα τοῖς ὑγιαίνουσιν ἢ οἷα τοῖς κάμνουσιν, καὶ βαρύτερα πότερον ἃ τοῖς ἀσθενοῦσιν ἢ ἃ τοῖς ἰσχύουσιν, καὶ ἀληθῆ πότερον ἃ τοῖς καθεύδουσιν ἢ ἃ τοῖς ἐγρηγορόσιν.
Next, it is a wonder if they are in doubt about this: whether magnitudes are of such a size and colors of such a kind as they appear to those at a distance or to those nearby; and whether they are such as they appear to the healthy or to the sick; and whether those things are heavier which seem so to the weak or to the strong; and whether those things are true which appear to the sleeping or to the waking.
ὅτι μὲν γὰρ οὐκ οἴονταί γε, φανερόν· οὐθεὶς γοῦν, ἐὰν ὑπολάβῃ νύκτωρ Ἀθήνῃσιν εἶναι ὢν ἐν Λιβύῃ, πορεύεται εἰς τὸ ᾠδεῖον.
For that they do not really think so is clear; at least, no one, if he supposes at night that he is in Athens when he is in Libya, sets out for the Odeum.
ἔτι δὲ περὶ τοῦ μέλλοντος, ὥσπερ καὶ Πλάτων λέγει, οὐ δήπου ὁμοίως κυρία ἡ τοῦ ἰατροῦ δόξα καὶ ἡ τοῦ ἀγνοοῦντος, οἷον περὶ τοῦ μέλλοντος ἔσεσθαι ὑγιοῦς ἢ μὴ μέλλοντος.
Furthermore, concerning the future, as Plato also says, the opinion of the physician and that of the ignorant person are surely not of equal authority, for example, about whether someone is going to be healthy or not.
ἔτι δὲ ἐπʼ αὐτῶν τῶν αἰσθήσεων οὐχ ὁμοίως κυρία ἡ τοῦ ἀλλοτρίου καὶ ἰδίου ἢ τοῦ πλησίον καὶ τοῦ αὑτῆς, ἀλλὰ περὶ μὲν χρώματος ὄψις, οὐ γεῦσις, περὶ δὲ χυμοῦ γεῦσις, οὐκ ὄψις· ὧν ἑκάστη ἐν τῷ αὐτῷ χρόνῳ περὶ τὸ αὐτὸ οὐδέποτε φησιν ἅμα οὕτω καὶ οὐχ οὕτως ἔχειν.
Furthermore, in the case of the senses themselves, the authority of a foreign sense and that of the proper sense, or that of a neighboring sense and that of its own, are not equal; but sight, not taste, is authoritative concerning color, and taste, not sight, concerning flavor; and none of these senses ever says at the same time, concerning the same thing, that it is both so and not so.
ἀλλʼ οὐδὲ ἐν ἑτέρῳ χρόνῳ περί γε τὸ πάθος ἠμφισβήτησεν, ἀλλὰ περὶ τὸ ᾧ συμβέβηκε τὸ πάθος.
Nor indeed at another time does a sense ever dispute about the affection itself, but only about that to which the affection happens.
λέγω δʼ οἷον ὁ μὲν αὐτὸς οἶνος δόξειεν ἂν ἢ μεταβαλὼν ἢ τοῦ σώματος μεταβαλόντος ὁτὲ μὲν εἶναι γλυκὺς ὁτὲ δὲ οὐ γλυκύς· ἀλλʼ οὐ τό γε γλυκύ, οἷόν ἐστιν ὅταν ᾖ, οὐδεπώποτε μετέβαλεν, ἀλλʼ ἀεὶ ἀληθεύει περὶ αὐτοῦ, καὶ ἔστιν ἐξ ἀνάγκης τὸ ἐσόμενον γλυκὺ τοιοῦτον.
I mean, for example, the same wine might seem, either because it has changed or because one's body has changed, to be at one time sweet and at another not sweet; but the sweet itself, such as it is when it exists, has never changed, but is always true about itself, and that which is to be sweet is of necessity of such a nature.
καίτοι τοῦτο ἀναιροῦσιν οὗτοι οἱ λόγοι ἅπαντες, ὥσπερ καὶ οὐσίαν μὴ εἶναι μηθενός, οὕτω μηδʼ ἐξ ἀνάγκης μηθέν· τὸ γὰρ ἀναγκαῖον οὐκ ἐνδέχεται ἄλλως καὶ ἄλλως ἔχειν, ὥστʼ εἴ τι ἔστιν ἐξ ἀνάγκης, οὐχ ἕξει οὕτω τε καὶ οὐχ οὕτως.
Yet all these arguments destroy this; just as they deny that there is any substance of anything, so they deny that anything is of necessity; for that which is necessary cannot be otherwise and otherwise, so that if anything is of necessity, it will not be both so and not so.
—ὅλως τʼ εἴπερ ἔστι τὸ αἰσθητὸν μόνον, οὐθὲν ἂν εἴη μὴ ὄντων τῶν ἐμψύχων· αἴσθησις γὰρ οὐκ ἂν εἴη.
And on the whole, if only the sensible exists, nothing would exist if animate things did not exist; for there would be no sensation.
τὸ μὲν οὖν μήτε τὰ αἰσθητὰ εἶναι μήτε τὰ αἰσθήματα ἴσως ἀληθές (τοῦ γὰρ αἰσθανομένου πάθος τοῦτό ἐστι), τὸ δὲ τὰ ὑποκείμενα μὴ εἶναι, ἃ ποιεῖ τὴν αἴσθησιν, καὶ ἄνευ αἰσθήσεως, ἀδύνατον.
Now, that neither the objects of sensation nor the sensations themselves exist is perhaps true (for this is an affection of the sensing subject), but that the underlying subjects which produce sensation do not exist, even without sensation, is impossible.
οὐ γὰρ δὴ ἥ γʼ αἴσθησις αὐτὴ ἑαυτῆς ἐστίν, ἀλλʼ ἔστι τι καὶ ἕτερον παρὰ τὴν αἴσθησιν, ὃ ἀνάγκη πρότερον εἶναι τῆς αἰσθήσεως· τὸ γὰρ κινοῦν τοῦ κινουμένου φύσει πρότερόν ἐστι, κἂν εἰ λέγεται πρὸς ἄλληλα ταῦτα, οὐθὲν ἧττον.
For sensation is surely not of itself, but there is also something else besides sensation, which must of necessity be prior to sensation; for that which moves is by nature prior to that which is moved, and this is no less true even if they are spoken of in relation to each other.
Notes
- 4.5#2ἐν δὲ τούτοις πολλὴ ἡ τοῦ ἀορίστου φύσις ἐνυπάρχει — The demonstrative pronoun τούτοις (neuter plural dative) refers back to the previously discussed 'opinions' or 'assumptions' of those who reduce being to the sensible. The term 'indeterminate' (ἀόριστον) points to the material, underlying reality which in potentiality (δυνάμει) can accommodate contraries, directly linking this argument to the discussion of potentiality in the preceding section.
- 4.5#2ἔτι δὲ πᾶσαν ὁρῶντες ταύτην κινουμένην τὴν φύσιν... — The participle construction (ὁρῶντες...) introduces the premise of their thought, but the main verb governing this clause (such as ὑπέλαβον, 'they supposed') is omitted, creating an anacoluthon. However, the logical connection is restored in the subsequent sentence starting with ἐκ γὰρ ταύτης τῆς ὑπολήψεως ('for from this supposition...'), which explains how this observation led to their extreme position.
- 4.5#2δικαιότερον ἂν διʼ ἐκεῖνα τούτων ἀπεψηφίσαντο ἢ διὰ ταῦτα ἐκείνων κατεψηφίσαντο — A contrary-to-fact conditional construction using the indicative past (ἀπεψηφίσαντο, κατεψηφίσαντο) with the particle ἄν. It indicates that it 'would have been more just' to acquit these (earthly, changing things) on the basis of those (celestial, changeless things), rather than to condemn those on the basis of these, implying that they did the latter.
- 4.5#2τὸ μὲν οὖν μήτε τὰ αἰσθητὰ εἶναι μήτε τὰ αἰσθήματα ἴσως ἀληθές — The neuter article τό substantivizes the following accusative-with-infinitve clause (μήτε τὰ αἰσθητὰ εἶναι μήτε τὰ αἰσθήματα), serving as the subject of the sentence. Aristotle points out that 'neither the objects of sensation nor the sensations themselves existing is perhaps true,' insofar as both are dependent on the affection (πάθος) of the sensing subject.
Cite this passage
Aristotle, Metaphysics §4.5#2. Humanitext Reader, https://reader.humanitext.ai/en/text/urn:cts:greekLit:tlg0086.tlg025.humanitext-grc2:4.5%232
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