The many and the one - the logic of plurals and its applications

This project is led by Dr Salvatore Florio and is funded by a Leverhulme Trust Research Fellowship.

Several natural languages contain a grammatical distinction between singular and plural expressions. When available, plural expressions play a critical role in thought and language.

While singular expressions enable us to convey information about single entities and their relations (e.g. ‘The Wonderful Wizard of Oz was published in 1900’ or ‘Desdemona loves Othello’), plural expressions enable us to convey information about collections of entities and their relations (e.g. ‘the natural numbers are infinite’ or ‘some critics admire only one another’). This information does not always appear to be expressible by means of singular expressions alone and, in this sense, plural expressions cannot be reduced to singular ones.

Moreover, plural expressions generate valid patterns of reasoning that go beyond those systematised in traditional logic, forming the subject matter of a new branch of logic known as plural logic. Plural logic has become an important component of the philosopher’s toolkit, finding applications in a variety of areas such as semantics, metaphysics, philosophy of mathematics, and philosophy of mind.

Salvatore’s research fellowship will develop a new perspective on plural logic and its philosophical significance by clarifying current controversies on the meaning and logic of plurals, by developing a novel semantics bridging the gap between philosophical and linguistic approaches, and by providing a critical evaluation of plural logic's applications in metaphysics, semantics, and philosophy of mathematics.

Salvatore began his 12-month fellowship in September 2017, and as part of his project will undertake a research visit at the University of Oslo to work with Professor Øystein Linnebo – the two will collaborate on a co-authored monograph arising from the project’s findings.