Keunikan manusia telah diklaim atas banyak alasan, tetapi paling sering karena pembuatan alat, budaya, bahasa, akal, dan moralitas kita. Kami memilikinya, hewan lain tidak, dan - begitulah argumennya - begitulah. Asli: The uniqueness of humans has been claimed on many grounds, but most often because of our tool-making, culture, language, reason and morality. We have them, the other animals don't, and - so the argument goes - that's that.

— Kata-kata Bijak dari Carl Sagan