Is that a Dog to you?

Words mean nothing. Language doesn’t stand for anything. How could this be true when we communicate orally? Or if language and words mean nothing how can you be reading and understanding this right now? It is true in that words point to something else, ideas. This way of thinking refers to Semiotics. Semiotics is the science of signs. Several things point to an idea of something else.
What makes a dog a dog? Four legs, a body, and a “ruff ruff” sound. Why do those things point to a dog? A Swiss linguist, Ferdinand de Saussure said that there is a gap or space between material expression and the meaning or interpretation of that expression. THIS + THIS = THIS or SIGNIFIER + SIGNIFIED= SIGN. A signifier represents the physical or material and the signified represents the idea. Together they make the sign of something. Communication takes place when the signifier and signified are added together.
The signifier and signified could also be looked at as:
IMAGE + IDEA= SIGN
OBJECT + SUBJECT = SIGN
EXPRESSION + PERCEPTION=SIGN
REAL + IDEAL= SIGN
Thus a “ruff ruff” sound would be a signifier and the idea that dogs make that sound would be the signified so together they point to a dog.
According to the American pragmatist, Charles Pierce there are three types of relationships between the signifier and signified. The first being a symbolic relationship were the relationship is arbitrary. The sign is a symbol like scales which can signify justice. The second type is indexical where the relationship is existential and the signs co-exist at some time. The sign is an index. The third type is iconic where the signifier structurally resembles its signified. The sign is an icon such as a statue or map. These types do not create categories rather help us understand the space between a signifier and signified.
In addition to SIGNIFER + SIGNIFIED = SIGN, Roland Barthes generated that there are three levels of signification. The first being denotation where the signifier is the image itself and the signified is an index like the dictionary definition of a word. Here one interprets only what they see and recognize. The second is connotation where denotation is used as a signifier and then that signifier creates another signified. The third is ideology where the signifier is combined with the denotative and connotative sign and then creates another signified. Ideology deals with society and how beliefs of society point to a sign. What something means or signifies is based on society's views and beliefs.
Signs make sense in relations and opposites. Happy does not make sense if one does not know what is sad. Semiotics is the science of signs and that everything points to something else. We communicate through adding something physical with an idea. Words are thus only sounds and letters. Language is an endless array of ideas more than words in a dictionary.