Sociology has long sought to find out how acting in a situation and observing that situation may differ and nevertheless belong to a single kind of social operation. George Spencer-Brown's Laws of Form (1969) provides one way to conceive of such an operation. The present book is the first to make sociological use of his mathematical calculus of form, which has been extensively applied to cybernetics, systems theory, cognitive science, and mathematics. Spencer-Brown's theory states that any action or communication is always an operation that makes a distinction. Not only does this...