"Not only the evident connection between breathing and emotion already urged, but also the belief that thoughts are words and words are breath—ἒττεα ἀέρια as Sappho seems to have called them—would lead to the belief that the organs of breath, the lungs, are the organs of mind. This conception of words would be natural, inevitable among men unfamiliar with writing. These words or thoughts are kept in the lungs."
— R.B. Onians, The Origins of European Thought, p67