Aristotle, Parva Naturalia. On Respiration

LCL 288: 430-431

Go To Section
Go To Section



470 b

I. Περὶ γὰρ ἀναπνοῆς ὀλίγοι μέν τινες τῶν πρότερον φυσικῶν εἰρήκασιν· τίνος μέντοι χάριν ὑπάρχει τοῖς ζῴοις, οἱ μὲν οὐδὲν ἀπεφήναντο, οἱ δὲ εἰρήκασι μέν, οὐ καλῶς δ᾿ εἰρήκασιν ἀλλ᾿ ἀπειροτέρως 10τῶν συμβαινόντων. ἔτι δὲ πάντα τὰ ζῷά φασιν ἀναπνεῖν· τοῦτο δ᾿ οὐκ ἔστιν ἀληθές. ὥστ᾿ ἀναγκαῖον περὶ τούτων πρῶτον ἐπελθεῖν, ὅπως μὴ δοκῶμεν ἀπόντων κενὴν κατηγορεῖν.

Ὅτι μὲν οὖν ὅσα πλεύμονα ἔχει τῶν ζῴων ἀναπνεῖ πάντα, φανερόν. ἀλλὰ καὶ τούτων αὐτῶν ὅσα μὲν ἄναιμον ἔχει τὸν πλεύμονα καὶ σομφόν, 15ἧττον δέονται τῆς ἀναπνοῆς· διὸ πολὺν χρόνον ἐν τοῖς ὕδασι δύνανται διαμένειν παρὰ τὴν τοῦ σώματος ἰσχύν. τὸν δὲ πλεύμονα σομφὸν ἔχει πάντα τὰ ᾠοτοκοῦντα, οἷον τὸ τῶν βατράχων γένος. ἔτι δὲ αἱ ἑμύδες τε καὶ χελῶναι πολὺν χρόνον μένουσιν 20ἐν τοῖς ὑγροῖς· ὁ γὰρ πλεύμων ὀλίγην ἔχει θερμότητα· ὀλίγαιμον γὰρ ἔχουσιν αὐτόν· ἐμφυσώμενος οὖν αὐτὸς τῇ κινήσει καταψύχει καὶ ποιεῖ διαμένειν πολὺν χρόνον. ἐὰν μέντοι βιάζηταί τις λίαν κατέχων πολὺν χρόνον, ἀποπνίγονται πάντα· οὐδὲν γὰρ τῶν τοιούτων δέχεται τὸ ὕδωρ ὥσπερ οἱ ἰχθύες.1 τὰ δ᾿ ἔναιμον ἔχοντα τὸν πλεύμονα


On Respiration

On Respiration

I. A few of the earlier natural philosophers haveAnimals and breathing. dealt with respiration; some of them have offered no explanation why this phenomenon occurs in living creatures; others have discussed it without much insight, and with insufficient experience of the facts. Again they say that all living creatures breathe; but this is not true. We must then first essay these questions, so that we may not be thought to be passing a baseless censure on men who are not there to defend themselves.

It is of course quite obvious that all animals with lungs breathe; but of these same animals such as have a bloodless or spongy lung need breathing less than the others; this is why they can remain in water a long time for their bodily strength. All oviparous animals, such as the genus frog, have a spongy lung. Again both the fresh-water and sea tortoises live under water for a long time; for the lung, containing little blood, has little heat; so when inflated it itself causes by its movement a cooling effect, and enables the tortoise to remain under water for a long time. But if one holds it down too long, an animal of this kind is drowned; for none of these animals can take in water like the fish. All animals whose lung contains

DOI: 10.4159/DLCL.aristotle-parva_naturalia_respiration.1957