. . . Unlike Dewey, he has provided detailed incisive argumentation, and has shown just where the dogmas and dualisms break down." -- Richard Rorty, The Yale Review.

In nelson goodman's "languages of art" a symbol system must be 'finitely differentiated', both syntactically and semantically, to count as a 'notation'. goodman's formulations of these differentiation requirements are seriously defective. it is shown that most of the examples of systems which he claims fail these requirements, do not fail them as they are stated. reformulations of the two requirements are offered, which accord with the examples and seem otherwise acceptable.

The purpose of this paper is to uncover and correct several confusions about expressions, tokens and the relations between them that crop up in even highly sophisticated writing about language and logic.

Locke’s thesis states that no two things of the same sort can be in the same place at the same time. The thesis has recently received extensive discussion, with some philosophers attempting to find arguments in its favour and others attempting to provide counter-examples. However, neither the arguments nor the counter-examples have been especially convincing; and it is my aim, in this short note, to present what I believe is a more convincing counter-example to the thesis.