This is the [IRG] — the interdisciplinary group dedicated to the investigation of iconic processes in art, science and literature.
Generally speaking, an iconic sign communicates a habit embodied in an object to the interpretant, so as to constrain the interpreter’s behavior, as a result of a certain quality that the sign and the object share.
When an “operational criterion” is adopted, the icon is defined as anything whose manipulation can reveal more information about your object, and algebra, syntax, graphs, and diagrams should be recognized as icons. In short, an icon is characterized as a sign that reveals information through a procedure followed by observation.
“A sign resembles its object if, and only if, study of the sign can yield new information about the object.” Chris Hookway.
We could say (sensu Wittgenstein) that the icon shows its meaning through its material form and structural organization.