Why should Logic be Considered as Semiotics by Peirce?
Zhang Liuhua
Abstract: First and foremost as a logician, C. S. Peirce in his mature phase orientated himself
to a new scientific system of logic. He at last insisted that logic as an integrated science should
be identified with semiotics, that is, the quasinecessary, or formal, doctrine of signs. This paper
attempts to clarify the meaning or significance of Peirce’s semiotic logicin the context of the
history and philosophy of logic, and then seeks to explain why Peirce had extended his logic project
from logic proper to semiotics by appealing to his basic ideas about logic’s role in pursuing truth.
Key words: scope of logic; semiotics; modern logic; mission
