Haldane guesses that a dog would probably be able to place the acids in the order of their molecular weights by their smells, just as a man could place a number of piano wires in the order of their lengths by means of their notes.
Haldane gætter på, at en hund sikkert ville kunne rangere syrerne efter molekylær vægt blot ved deres lugt, ligesom en mand kunne rangere et antal klaverstrenge efter længde blot ved lyden af deres toner.