Discussing Gottlob Frege's "Sense and Reference," "Concept and Object" (both from 1892) and "The Thought" (1918), which you can obtain via this book..
What is it about sentences that make them true or false? Frege, the father of analytic philosophy who invented modern symbolic logic, attempted to codify language in a way that would make this obvious, which would ground mathematics and science. Applying his symbolic system to natural language forced him to invent strange entities like "thoughts" and "senses" that are neither physical nor psychological, and we pretty much spend this episode kvetching about the metaphysical implications of this and the fact that Frege didn't care about them.
Running Time: 1 hr., 48 min. Recorded: February 20, 2011. Participants: Mark, Wes, Seth, and Matt Teichman
As a bonus, your purchase includes a high-bitrate mp3 of the song that concludes the episode, "The Great Forgotten Lover," by New People, from the album Impossible Things (2011).