Laudator Temporis Acti

Horace, Odes 4.4.29-32 (tr. Niall Rudd):

The brave are born from the brave and good. Their sire's valour comes out in young bulls and horses; ferocious eagles do not father timid doves.

Fortes creantur fortibus et bonis;
est in iuvencis, est in equis patrum
  virtus, neque inbellem feroces
  progenerant aquilae columbam.

Theognis 535-538 (tr. Dorothea Wender):

Slave heads don't ever stand up straight, they grow
Tipped down in servitude, their backs bent low;
No rose or hyacinth comes from the wild
Squill, not does a slave bear a free child.

οὔποτε δουλείη κεφαλὴ ἰθεῖα πέφυκεν,
  ἀλλ' αἰεὶ σκολιὴ, καὐχένα λοξὸν ἔχει.
οὔτε γὰρ ἐκ σκίλλης ῥόδα φύεται οὐδ' ὑάκινθος,
  οὔτε ποτ' ἐκ δούλης τέκνον ἐλευθέριον.

Lucretius 3.741-752 (tr. Martin Ferguson Smith):

Furthermore, why does bitter fury go with the sullen breed of lions, why craft with foxes, why is the instinct of flight transmitted to deer from their fathers, the father's timidity impelling their limbs, why are all other qualities of this sort generated in the body and the character from the beginnings of life, if not because in each seed and breed its own fixed power of mind grows along with each body? But if it were immortal, and accustomed to pass from body to body, living creatures would show confused habits: the dog of Hyrcanian breed would often flee before the horned stag's onset; the hawk would tremble, flying through the air from the advancing dove; men would lack reason, the wild generations of wild beasts would have it.

Denique cur acris violentia triste leonum
seminium sequitur, volpes dolus, et fuga cervis
a patribus datur et patrius pavor incitat artus?
et iam cetera de genere hoc cur omnia membris
ex ineunte aevo generascunt ingenioque,
si non, certa suo quia semine seminioque
vis animi pariter crescit cum corpore quoque?
quod si inmortalis foret et mutare soleret
corpora, permixtis animantes moribus essent:
effugeret canis Hyrcano de semine saepe
cornigeri incursum cervi tremeretque per auras
aeris accipiter fugiens veniente columba;
desiperent homines, saperent fera saecla ferarum.

In all three passages, the rhetorical trope known as adynaton (impossibility) is joined to the theme of the hereditary nature of qualities.