lation to each other.  Moreover, the
     definition of the cartesian product, that comes into the
     game as soon as we start to develop the theory of signs
     along extensional lines, and which is almost inevitable
     if we want to use sign relations as models of empirical
     activities and natural forms of conduct, already brings
     us the utilities of the various dimensional projections.
     So my purpose here was more to elucidate or rationalize
     the Categories as aspects or facets of 3-