We all know there are precedents from which common design elements and styles were established and then "borrowed from."
However, how much of a design and its expression derived from historial precedent must and can be considered to establish the design was plaigarized and built by others when the person's design being plaigarized is itself derived frrom historical precedents?
How can we possibly establish the meaning and the scope of "how much?" I know what I was taught in school and in practice about the vocabulary of architecture but where does plaigarism begin and end?. What would your criteria be? Could your criteria be substantiated formally or "officially?"