When one studies the work of Karl Popper, one sooner or later will discover the various passages in which Popper insists that one makes a distinction between a 3rd descriptive and 4th argumentative function of language. That distinction first showed up in a presentation in 1948. And it continued showing up in original work written as late as 1992.
I compiled all the sections in which Popper discussed this distinction and put them together in an online document publicly available document at https://docs.google.com/document/d/1n0_vbvxY4jOfRimUytDfabium1NDhvKXZC1JBnRj6Cw/edit where one can leave comments which is encouraged.
Who is interested in studying this distinction in the work of Popper and why philosophers have ignored it, as if they have decided, collectively, that this distinction is so embarrassingly trivial that it is better to ignore that Popper spent so much time and effort on arguing it?
To be sure, this is not to argue that no one has ever discussed or mentioned this distinction. Instead, it is to raise the question why so few people have picked it up and done something interesting with it. For example, consider the work of Richard Bailey (2000), Edward Feser’s (2011) Hayek, Popper and the Causal Theory of the Mind, Alex Naraniecki’s (2014) Returning to Karl Popper. A reassessment of his politics and philosophy, and Shearmur & Stokes (2016) Cambridge Campanion to Karl Popper. Feser (2011) is particularly noteworthy.
If you would like to learn more about the project of studying this intriguing lack, send an email to ourkarlpopper@gmail.com.
Margaretha Hendrickx, Trumansburg, NY, USA
How Karl Popper Has Made a Difference in Our Lives 