Reality is a system of signs
In the final paragraph of the introduction to Semiotics for Beginners by Daniel Chandler, he writes (I’ve broken it into shorter paragraphs for easier reading):
Semiotics is important because it can help os not to take “reality” for granted as something having a purely objective existence which is independent of human interpretation. It teaches us that reality is a system of signs. Studying semiotics can assist us to become more aware of reality as a construction and of of the roles played by ourselves and others in constructing it.
[Studying semiotics] can help us to realize that information or meaning is not “contained” in the world or in books, computers or audio-visual media. Meaning is not “transmitted” to us—we actively create it according to a complex interplay of codes or conventions of which we are normally unaware. […]
The study of signs is the study of the construction and maintenance of reality