SYMBOL

It may be safe to say that a sign that is not an icon or an index is a symbol, but such a definition is cavalier and not insightful. A symbol can be defined as a sign that realizes its object. That is, there is a rule or law which bind the symbol and the object so that the symbol denotes without particularizing.

As an example, a word may be considered a symbol. The word dog realizes and denotes the concept of dog without particularly referring to any specific one[2]. Additionally, the word dog seems to be an arbitrary binding of the symbol and its object. This binding is characterized as a rule or law that simply states that the symbol and the object are one.

Icons, indices and symbols permeate engineering design. Through this work, the techniques of feature abstraction, rule representation, and information flows as well as user-computer interactions and computer-computer interactions can be examined in terms of signs and their underlying "meanings". As will be seen, sign systems may be buried within other sign systems, which in turn are buried within others, and so on. An observation of the signs and sign systems used allows a view of concurrent engineering design in terms of a linguistic and social phenomena.