… a definitely significant Form, I propose to term a Type. A Single event which happens once and whose identity is limited to that one happening or a Single object or thing which is in some single place at any one instant of time, such event or thing being significant only as occurring just when and where it does, such as this or that word on a single line of a single page of a single copy of a book, I will venture to call a Token. An indefinite significant character such as a tone of voice can neither be called a Type nor a Token. I propose to call such a Sign a Tone.
A Sign may itself have a “possible” Mode of Being. E.g. A hexagon inscribed in or circumscribed about a conic. It is a Sign, in that the collinearity of the intersections of opposite sides shows the curve to be a conic, if the hexagon is inscribed; but if it be circumscribed the copunctuality of its three diameters (joining opposite vertices.) Its mode of Being may be Actuality: as with any barometer. Or Necessitant: as the word “the” or any other in the dictionary. For a “possible” Sign I have no better designation than a Tone, though I am considering replacing this by “Mark.” [—] An Actual sign I call a Token; a Necessitant Sign a Type.