4. It is not thus with us. Why? Because we incessantly move the ancient landmarks which our fathers have set.  21  cf. Prov. xxii. 28. We encroach, we add house to house, field to field, to enrich ourselves at the expense of our neighbour. The great fish know the sojourning place that nature has assigned to them; they occupy the sea far from the haunts of men, where no islands lie, and where are no continents rising to confront them, because it has never been crossed and neither curiosity nor need has persuaded sailors to tempt it. The monsters that dwell in this sea are in size like high mountains, so witnesses who have seen tell us, and never cross their boundaries to ravage islands and seaboard towns. Thus each kind is as if it were stationed in towns, in villages, in an ancient country, and has for its dwelling place the regions of the sea which have been assigned to it.

Instances have, however, been known of migratory fish, who, as if common deliberation transported them into strange regions, all start on their march at a given sign. When the time marked for breeding arrives, they, as if awakened by a common law of nature, migrate from gulf to gulf, directing their course toward the North Sea. And at the epoch of their return you may see all these fish streaming like a torrent across the Propontis towards the Euxine Sea. Who puts them in marching array? Where is the prince’s order? Has an edict affixed in the public place indicated to them their day of departure? Who serves them as a guide? See how the divine order embraces all and extends to the smallest object. A fish does not resist God’s law, and we men cannot endure His precepts of salvation! Do not despise fish because they are dumb and quite unreasoning; rather fear lest, in your resistance to the disposition of the Creator, you have even less reason than they. Listen to the fish, who by their actions all but speak and say: it is for the perpetuation of our race that we undertake this long voyage. They have not the gift of reason, but they have the law of nature firmly seated within them, to show them what they have to do. Let us go, they say, to the North Sea. Its water is sweeter than that of the rest of the sea; for the sun does not remain long there, and its rays do not draw up all the drinkable portions.  22  cf. Arist., Hist. Animal. viii. 12 and 13, and note on p. 70. Even sea creatures love fresh water.  23  cf. Arist. and Theophrastus. Thus one often sees them enter into rivers and swim far up them from the sea. This is the reason which makes them prefer the Euxine Sea to other gulfs, as the most fit for breeding and for bringing up their young. When they have obtained their object the whole tribe returns home. Let us hear these dumb creatures tell us the reason. The Northern sea, they say, is shallow and its surface is exposed to the violence of the wind, and it has few shores and retreats. Thus the winds easily agitate it to its bottom and mingle the sands of its bed with its waves. Besides, it is cold in winter, filled as it is from all directions by large rivers. Wherefore after a moderate enjoyment of its waters, during the summer, when the winter comes they hasten to reach warmer depths and places heated by the sun, and after fleeing from the stormy tracts of the North, they seek a haven in less agitated seas.

Ἀλλ' οὐχ ἡμεῖς τοιοῦτοι. Πόθεν; Οἵγε μεταίρομεν ὅρια αἰώνια, ἃ ἔθεντο οἱ πατέρες ἡμῶν. Παρατεμνόμεθα γῆν, συνάπτομεν οἰκίαν πρὸς οἰκίαν καὶ ἀγρὸν πρὸς ἀγρὸν, ἵνα τοῦ πλησίον ἀφελώμεθά τι. Οἶδε τὰ κήτη τὴν ἀφωρισμένην αὐτοῖς παρὰ τῆς φύσεως δίαιταν, τὴν ἔξω τῶν οἰκουμένων χωρίων κατείληφε θάλασσαν, τὴν ἐρήμην νήσων, ᾗ μηδεμία πρὸς τὸ ἀντιπέρας ἀντικαθέστηκεν ἤπειρος. Διόπερ ἄπλους ἐστὶν, οὔτε ἱστορίας, οὔτε τινὸς χρείας κατατολμᾶν αὐτῆς τοὺς πλωτῆρας ἀναπειθούσης. Ἐκείνην καταλαβόντα τὰ κήτη, τοῖς μεγίστοις τῶν ὀρῶν κατὰ τὸ μέγεθος ἐοικότα, ὡς οἱ τεθεαμένοι φασὶ, μένει ἐν τοῖς οἰκείοις ὅροις, μήτε ταῖς νήσοις, μήτε ταῖς παραλίοις πόλεσι λυμαινόμενα. Οὕτω μὲν οὖν ἕκαστον γένος, ὥσπερ πόλεσιν ἢ κώμαις τισὶν ἢ πατρίσιν ἀρχαίαις, τοῖς ἀποτεταγμένοις αὐτοῖς τῆς θαλάσσης μέρεσιν ἐναυλίζεται. Ἤδη δέ τινες καὶ ἀποδημητικοὶ τῶν ἰχθύων, ὥσπερ ἀπὸ κοινοῦ βουλευτηρίου πρὸς τὴν ὑπερορίαν στελλόμενοι, ὑφ' ἑνὶ συνθήματι πάντες ἀπαίρουσιν. Ἐπειδὰν γὰρ ὁ τεταγμένος καιρὸς τῆς κυήσεως καταλάβῃ, ἄλλοι ἀπ' ἄλλων κόλπων μεταναστάντες, τῷ κοινῷ τῆς φύσεως νόμῳ διεγερθέντες, ἐπὶ τὴν βορινὴν ἐπείγονται θάλασσαν. Καὶ ἴδοις ἂν κατὰ τὸν καιρὸν τῆς ἀνόδου ὥσπερ τι ῥεῦμα τοὺς ἰχθῦς ἡνωμένους, καὶ διὰ τῆς Προποντίδος ἐπὶ τὸν Εὔξεινον ῥέοντας. Τίς ὁ κινῶν; ποῖον πρόσταγμα βασιλέως; ποῖα διαγράμματα κατ' ἀγορὰν ἡπλωμένα τὴν προθεσμίαν δηλοῖ; οἱ ξεναγοῦντες τίνες; Ὁρᾷς τὴν θείαν διάταξιν πάντα πληροῦσαν, καὶ διὰ τῶν μικροτάτων διήκουσαν. Ἰχθὺς οὐκ ἀντιλέγει νόμῳ Θεοῦ, καὶ ἄνθρωποι σωτηρίων διδαγμάτων οὐκ ἀνεχόμεθα. Μὴ καταφρόνει τῶν ἰχθύων, ἐπειδὴ ἄφωνα καὶ ἄλογα παντελῶς, ἀλλὰ φοβοῦ μὴ καὶ τούτων ἀλογώτερος ᾖς, τῇ διαταγῇ τοῦ κτίσαντος ἀνθιστάμενος. Ἄκουε τῶν ἰχθύων μονονουχὶ φωνὴν ἀφιέντων δι' ὧν ποιοῦσιν, ὅτι εἰς διαμονὴν τοῦ γένους τὴν μακρὰν ταύτην ἀποδημίαν στελλόμεθα. Οὐκ ἔχουσιν ἴδιον λόγον, ἔχουσι δὲ τὸν τῆς φύσεως νόμον ἰσχυρῶς ἐνιδρυμένον, καὶ τὸ πρακτέον ὑποδεικνύντα. Βαδίσωμεν, φασὶν, ἐπὶ τὸ βόρειον πέλαγος. Γλυκύτερον γὰρ τῆς λοιπῆς θαλάσσης ἐκεῖνο τὸ ὕδωρ, διότι ἐπ' ὀλίγον αὐτῇ προσδιατρίβων ὁ ἥλιος, οὐκ ἐξάγει αὐτῆς ὅλον διὰ τῆς ἀκτῖνος τὸ πότιμον. Χαίρει δὲ τοῖς γλυκέσι καὶ τὰ θαλάσσια: ὅθεν καὶ ἐπὶ τοὺς ποταμοὺς ἀνανήχεται πολλάκις, καὶ πόρρω θαλάσσης φέρεται. Ἐκ τούτου προτιμότερος αὐτοῖς ὁ Πόντος τῶν λοιπῶν ἐστι κόλπων, ὡς ἐπιτήδειος ἐναποκυῆσαι καὶ ἐκθρέψαι τὰ ἔκγονα. Ἐπειδὰν δὲ τὸ σπουδαζόμενον ἀρκούντως ἐκπληρωθῇ, πάλιν πανδημεὶ πάντες ὑποστρέφουσιν οἴκαδε. Καὶ τίς ὁ λόγος, ἀκούσωμεν παρὰ τῶν σιωπώντων. Ἐπιπόλαιος, φασὶν, ἡ βορεινὴ θάλασσα, καὶ ὑπτία προκειμένη τῶν ἀνέμων ταῖς βίαις, ὀλίγας ἀκτὰς καὶ ὑποδρομὰς ἔχουσα. Διὸ καὶ ἐκ πυθμένος οἱ ἄνεμοι ῥᾳδίως αὐτὴν ἀναστρέφουσιν, ὡς καὶ τὴν βυθίαν ψάμμον τοῖς κύμασιν ἀναμίγνυσθαι. Ἀλλὰ καὶ ψυχρὰ, χειμῶνος ὥρᾳ, ὑπὸ πολλῶν καὶ μεγάλων ποταμῶν πληρουμένη. Διὰ τοῦτο ἐφ' ὅσον μέτριον ἀπολαύσαντες αὐτῆς ἐν τῷ θέρει, πάλιν χειμῶνος ἐπὶ τὴν ἐν τῷ βυθῷ ἀλέαν καὶ τὰ προσήλια τῶν χωρίων ἐπείγονται, καὶ φυγόντες τὸ δυσήνεμον τῶν ἀρκτῴων, τοῖς ἐπ' ἔλαττον τινασσομένοις κόλποις ἐγκαθορμίζονται.