Charles Sanders Peirce

Father of Pragmatism and Semiotics - the study of symbols

C. S. Peirce was a man of remarkable achievement in the realms of science and philosophy.  Particularly interesting to a "theory of everything" like ADEPT, is his original work in the realm of semiotics - the exploration and ordering of symbols and their meaning in experience and reality.

The Translation nature is where such considerations exist within the ADEPT schema and so an interesting outcome of ADEPT is its ability to interpret Peirce's semiotics as a set of logically related graph concepts.  That is the nature of what will be presented here.


Peirce is well known for the way that he looked at seemingly everything through a lens of first-ness, second-ness and third-ness.  In semiotics he named the three ways in which a sign can relate to its object: as an icon (1st), an index (2nd) or a symbol (3rd).  This relational trichotomy was extended in a second dimension of three parts to represent the material and formal aspects of the original relational trichotomy. This produced three trichotomies, a 3x3 grid, or a 9-fold categorization of signs to which he gave the following names as well as examples:

  1. material quality: qualisign
  2. material indexicality: signsign
  3. material mediation: legisign
  4. relational quality: icon
  5. relational indexicality: index
  6. relational mediation: symbol
  7. formal quality: rheme
  8. formal indexicality: dicent sign
  9. formal mediation: argument

Building further upon this categorization of signs, Peirce presented 10 classes of Signs which presented the logical methods of interaction between the categories of signs.  Not surprisingly, this again followed a path of associating three things together.  Because of a a logical hierarchy that he saw at work in these classes, only certain collections of three sign types are able to form classes.  His classes, with examples were as follows:

  1. First Class  (I): "Qualisign" - a vague feeling (of "red"). Consists of a qualisign, an icon and a rheme.
  2. Second Class (II): "Iconic Sinsign" - an individual diagram. Consists of a sinsign, an icon and a rheme.
  3. Third Class (III): "Rhematic Indexical Sinsign" - a spontaneous cry. Consists of a singsign, an index and a rheme.
  4. Fourth Class (IV): "Dicent Sinsign" - a weather vane. Consists of a sinsign, and index and a dicent sign.
  5. Fifth Class (V): "Iconic Legisign" - a diagram, apart fromits factual individuality (which is 2nd class).  Consists of a legisign, an icon and a rheme.
  6. Sixth Class (VI): "Rhematic Indexical Legisign" - a demonstrative pronoun. Consists of a legisign, an index and a rheme.
  7. Seventh Class (VII): "Dicent Indexical Legisign" - a street cry or commonplace expression. Consists of a legisign, an index and a dicent sign.
  8. Eighth Class (VIII): "Rhematic Symbol" - a common noun, term or word. Consists of a legisign, a symbol and a rheme.
  9. Ninth Class (IX): "Dicent Symbol" - an ordinary proposition. Consists of a legisign, a symbol and a dicent sign.
  10. Tenth Class (X): "Argument" - a text. Consists of a legisign, a symbol and an argument.


As can be seen in the diagrams below, Peirce's semiotics provides a logical and interpretaive framework by which the ADEPT manifest translations of the second consideration can be understood both as isolated symbolic elements and as more complex constructions of symbolism.

Charles Sanders Peirce (b. 1839, d. 1914)
Charles Sanders Peirce (b. 1839, d. 1914)