The Curious Relation between Ideology and Logic

Max Cresswell

On January 14th 2022, with the purpose of celebrating the UNESCO World Logic Day, the Australasian Association for Logic will host a Southern Summer Logic Day. The event will take place on Zoom (contact Guillermo Badia at g.badia@uq.edu.au for the Zoom link). There will be one invited keynote presentation by Max Cresswell.

It is known that Willard van Orman Quine had an antipathy to modal logic in general and to modal predicate logic in particular. While that dispute is known to modal logicians it has always seemed to many of us that there must be more to the story than that. Apart from Quine and Marcus I will mention another American logician, William Tuthill Parry. Both Quine an Parry were in Germany in the 1930s. Among the Continental logicians I will mention Oskar Becker and Rudolf Carnap, and talk about the connection between political ideology in Germany at that time, and the differing philosophical ideologies (essentially metaphysics vs logical positivism). I will then look at how these differences affected attitudes to modal logic.

I will then move to the political situation in the United States in the 1950s and and mention the communist views of Parry and the socialist background of Ruth Barcan.

Finally I will point out how all these factors affect attitudes to quantified modal logic in a way in which from Quine's perspective Marcus ticked all the wrong boxes.

This talk will be about logic but will not be a technical talk and should be accessible to anyone with an interest in the topic.


Guillermo Badia (University of Queeensland, Australia)

Nick J J Smith (University of Sydney, Australia)

Shawn Standefer (National Taiwan University, Taiwan)

Zach Weber (University of Otago, New Zealand)