It is common to describe language use in terms of the rules that one follows, and Wittgenstein considers rules in some detail. He famously suggests that any act can be made out to follow from a given rule.[20] He does this in setting up a dilemma:
This was our paradox: no course of action could be determined by a rule, because every course of action can be made out to accord with the rule. The answer was: if everything can be made out to accord with the rule, then it can also be made out to conflict with it. And there would be neither accord nor conflict here.[21]
One can give an explanation of why one followed a particular rule in a particular case. But any explanation for rule following behaviour cannot be given in terms of following a rule, without involving circularity. One can say something like "She did X because of the rule R" but if you say "She followed R because of the rule R1" one can then ask "but why did she follow rule R1?" and so potentially become involved in a regression. Explanation must have an end.[22]
His conclusion: