Browsing All Posts filed under »Philosophy of Math«

Discovery and Invention Part I: Distinctions and Notations

December 6, 2018 by


In this three part (probably) series, I’m going to look at the notions of invention and discovery as they relate to how we think about mathematics and logic. In this first post, I’m going to set up the distinction between discovery and invention as I see it, and then talk about whether systems of notation for […]

Grinworthy Quotes (16): Self-promotion Edition

October 8, 2018 by

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I just had a co-authored (with Eamon Darnell) paper that’s based on a chapter of my dissertation (both titled “Is Hume’s Principle Analytic?” — link to preprint of the paper) accepted for publication (yay!). Near the end of the paper, we raise an issue that seems (to me at least) to have been under the surface […]

Frege and Hume at Thanksgiving

October 2, 2018 by

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It’s almost Thanksgiving here in Canada, so here’s a thanksgiving themed post about concepts from Frege and Neo-logicism. In his Grundlagen (1884), Frege proposes that the number that belongs to two concepts is the same just in case the objects falling under those concepts can be correlated one-to-one (i.e. they’re equinumerous). The formalization of that claim is […]

It’s a Small World: The Leśniewski-Sobociński Theorem.

February 21, 2018 by


The other day I was reading M. Resnik’s Frege and the Philosophy of Mathematics (1980). In discussing `Frege’s way out’, he mentions a proof by Leśniewski showing that Frege’s attempted fix to the system of the Grundgesetze is inconsistent, but gives a reference to a paper published by Sobociński in 1949. This intrigued me, as […]

Grinworthy Quotes (15)

February 16, 2018 by

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Frege on Euclidean geometry and axioms, but also astrology and alchemy. From his Nachlass*. Now the question is whether to strike Euclidean or non-Euclidean geometry from the ranks of science and to put it alongside of Alchemy and Astrology as mummies. Where one only let himself toy with ideas, he need not take things so […]

Grinworthy Quotes 14

January 18, 2018 by

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In discussing the possibility of adopting category theory as a (the) foundations for mathematics, Jean-Pierre Marquis has this to say in his Stanford Encyclopedia article (2015): To use a well-known metaphor: from a categorical point of view, Neurath’s ship has become a spaceship. I hope there is a literature developing about Neurath’s spaceship.

The Further Adventures of Hero and Hera.

September 27, 2017 by

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Those familiar with the neo-logicism literature, may also be familiar with the characters Hero and Hera. Hero was introduced by Crispin Wright in the late `90s, and the story Hero and his sister Hera was fleshed out by Philip Ebert and Marcus Rossberg in 2007*. In that paper, we learn that Hero and Hera both […]

Teaching as a Grad Student: Guest Lecturing on Logicism

April 26, 2017 by

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I was recently given the opportunity to give a lecture on Frege’s logicism and related topics for our Logic III course (cross-listed as an undergraduate and a graduate course). That class had gotten up to the point of looking at second-order Peano Arithmetic, which is a natural jumping off point for looking at the logic […]

Goldilocks, Bad Company and some Slippery Fish

February 28, 2017 by

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No this isn’t a terrible (amazing?) fairy tale. And no, the title isn’t (just) badly thought out clickbait. The Bad Company problem, the Goldilocks problem and the Problem of Fishiness are all problems I’m writing about in my dissertation. More specifically, the overarching idea is to look at ways of solving the Bad Company problem. […]

Is the Universe Part of the World?

June 11, 2016 by

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First let me head off the suspicion that I’ll be discussing some sort of weird idealist/massively subjectivist/etc metaphysics. I’m concerned with ‘world’ and ‘universe’ as they’re used by analytic metaphysicians, logicians, and philosophers of mathematics. In particular I’m concerned about the cardinalities of the domains of discourse assumed by some philosophers when dealing with, in […]

Grinworthy Quotes (10)

November 5, 2015 by

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Here’s other amusing line from Paul Benacerraf’s dissertation (Princeton, 1960, p. 182): It was in fact through [Cantor’s] interest in the infinite and in infinite numbers that he developed the theory of sets. The purpose was to make an honest woman of the infinite, a task held by most mathematicians of his time to be […]

Grinworthy Quotes (9)

October 8, 2015 by

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I know it’s been a while since I’ve posted one of these — I’ve been reading some fairly dry material recently. The following quote is at the very beginning of Paul Benacerraf’s unpublished PhD dissertation (Princeton, 1960) which I’m reading as part of my dissertation research. The quote is attributed to an unnamed undergraduate student. […]

Grinworthy Quotes (8)

June 5, 2015 by

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Here is another quote from John Burgess, this time from his book Fixing Frege (Princeton University Press: 2005). Anyone who reads logic/mathematics/philosophy of mathematics will have come across the phenomenon he’s talking about. Now it is a common mathematical practice, called “abuse of language,” to omit to distinguish notationally between items that are distinct notionally, […]


April 26, 2015 by

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A while back I was reading a paper  by Bob Hale and Crispin Wright, first published in 2000 [1], in which they use the symbol “#” to denote an arbitrary matrix sentence. That was over half a decade before twitter went live. That symbol, variously known as the hash sign/symbol, the number sign, or octothorpe […]

Grinworthy Quotes (7)

March 14, 2015 by

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Here is John Burgess’s amusing description of Quine’s view of mathematical ontology as motivated by the indispensability argument, from “Mathematics and the Bleak House” (Phil. Math. 12, 2004). Quine…urged a very different sort of reason for accepting the existence of numbers (or other abstract mathematical entities to which numbers could be “reduced”).  According to Quine, […]

Deflationism, Conservativity, Truth.

October 19, 2014 by


Over the summer I spent a lot of time learning about truth, and particularly deflationary theories of truth. In this post I will outline some of my thoughts about one particular criterion that is often argued for (and against) by various players in the recent literature on deflationism about truth: conservativity. The plan is to […]

Grinworthy Quotes (1)

October 1, 2014 by


Justin Caouette suggested to me that I start posting some of the amusing, and sometimes shocking philosophical quotations that I come across, and often share with him. This will be an on going series, though it is a matter of what I happen to be reading at any given time. The reason I have been […]

Bleg: Philosophy survey for mathematicians (From Logblog)

July 23, 2014 by

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There’s a new survey about the intuitions of mathematicians which will be very helpful for philosophers of mathematics (like me). Here is Richard Zach’s original post: A group of researchers in philosophy, psychology and mathematics are requesting the assistance of the mathematical community by participating in a survey about mathematicians’ philosophical intuitions. The survey is […]

Philosophy of Mathematics?

June 23, 2014 by


I work primarily in the philosophy and history of mathematics which has naturally led to discussion about the philosophy of mathematics with people outside my field, and outside of philosophy. In this post I will try to address, in a loose and (mostly) non-technical way, some of the questions that often arise in such discussions. […]