(Diaphragma), in Anatomy, a part vulgarly called the midriff, and by anatomists septum transversum. It is a strong muscular substance, separating the breast or thorax from the abdomen or lower venter, and serving as a partition between the abdominal and the thoracic viscera. See ANATOMY Index. Plato, as Galen informs us, first called it diaphragm, from the verb διαφράζειν, to separate or be between two. Till his time it had been called φρένις, from a notion that an inflammation of this part produced frenzy; which is not more warranted by experience than another tradition, that a transverse section of the diaphragm with a sword causes the patient to die laughing.

DIAPHORESIS, (Διαφορεσις), in Rhetoric, is used to express the hesitation or uncertainty of the speaker.

We have an example in Homer, where Ulysses, going to relate his sufferings to Alcinous, begins thus;

Τι πρῶτον τι δ’ ἐπίλη, τι δ’ ὑπὸν καταλήκῃ; Quid primum, quid deinde, quid postremo alloquar?

This figure is most naturally placed in the exordium or introduction to a discourse. See DOUBTING.