Journal of Philosophical Logic

, Volume 41, Issue 5, pp 853–875

Modalising Plurals


DOI: 10.1007/s10992-011-9194-2

Cite this article as:
Hewitt, S.T. J Philos Logic (2012) 41: 853. doi:10.1007/s10992-011-9194-2


There has been very little discussion of the appropriate principles to govern a modal logic of plurals. What debate there has been has accepted a principle I call (NecInc); informally if this is one of those then, necessarily: this is one of those. On this basis Williamson has criticised the Boolosian plural interpretation of monadic second-order logic. I argue against (NecInc), noting that it isn’t a theorem of any logic resulting from adding modal axioms to the plural logic PFO+, and showing that the most obvious formal argument in its favour is question begging. I go on to discuss the behaviour of natural language plurals, motivating a case against (NecInc) by developing a case that natural language plural terms are not de jure rigid designators. The paper concludes by developing a model theory for modal PFO+ which does not validate (NecInc). An Appendix discusses (NecInc) in relation to counterpart theory.


Second-order logicPlural quantificationModal logic

Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Department of PhilosophyBirkbeck College, University of LondonLondonUK