M. [Théodore] Flournoy includes all the phenomena of Colored Hearing
and of Mental Forms
under the convenient and adequate name Synæsthesia—in place of which, to be sure, he himself usually employs the less defensible term Synopsie. […] The phenomena of synæsthesia are divided into three main groups: photisms,
among which are included, as by [Eugen] Bleuler and Lehmann, all the varieties of pseudo-chromesthesia; Schemes,
comprising not only forms
(diagrammes) associated with series of words or numbers, but symbols,
or particular figures associated with single letters, numerals, colors and the like; and personifications,
in which the associated factor is no mere color or form, but has become richer and more concrete.