What is the difference between a polyneme and a pronome? "The difference is that a pronome has essentially the same effect on each of its recipients -- namely, to activate or to assign a certain short-term memory-unit. I'll introduce a new word -- 'isonome' -- for any agent that has this sort of uniform effect on many agencies."
Isonomes would be expected to exist because different agencies might have many structual similarities. Pronomes are only one type of isonome. "The power of polynemes stems from how they learn to arouse many different processes at once, while isonomes draw their power from exploiting abilities that are already common to many agencies."
NB: The move to name different types of processes with respect to this property (i.e., same vs. different effects) is striking. Does it suggest that other crucial architectural differences must also be true of isonomes vs. polynemes?