> A bunch of logical signs were invented by Frege This is true. I find Peirce's existential graphs interesting because they permit stating existential and univ

> A bunch of logical signs were invented by Frege This is true. I find Peirce's existential graphs interesting because they permit stating existential and universal quantifiers without any explicit syntax! Frege's work evidently has priority by about 4 years, but it doesn't appear that Peirce was aware of it.