Lamentarsi è una caratteristica innata della specie umana. Nel Secolo del Carbone la gente imprecava contro la macchina a vapore; in una commedia di … - Isaac Asimov

Humanity today forms a single species and can interbreed freely. Differences in color of hair, skin and eyes are largely due to differences in the quantity of a pigment called melanin, and this does not affect humanity's essentially unitary character. Nor do differences in the shape of the eye or nose, in the shape of the skull, or in height.

Πέρασα αυτές τις δύο μέρες εξετάζοντας εντατικά τον εαυτό μου", είπε ο Κιούτι, "και τα συμπεράσματα ήταν πολύ ενδιαφέροντα. Άρχισα από την μόνη βέβαιη υπόθεση που νόμιζα ότι μπορούσα να κάνω. Εγώ ο ίδιος υπάρχω, επειδή σκέπτομαι".
Ο Πάουελ αναστέναξε: "Ω, Θεέ μου,ο Καρτέσιος ρομπότ.

Freedom is a priceless thing, Sir," Andrew said. "And the chance of gaining my freedom is worth any amount of money that I may possess.