Ought to do’sOught to be’s
Rule of actionRule of reflection
If you’re in circumstances , do Pattern based judgment
Conceptually articulatedNot necessarily conceptually articulated
Rules of deliberationRule of assessment/criticism
First personalThird personal judgment of some behavior
What’s appropriate for me to do?Given what you did, was it appropriate?
The person subject to the rule is the one following the ruleThere may be no particular agent at all
Examples? TODO!“One ought to feel sympathy for the bereaved”
“All clocks should strike midnight at the same time.”
“Plants ought to get enough water to flower.”
  • A distinction fundamental for both ‘must’ in the alethic and doxastic modal senses.

  • Sellars: You can’t understand either of these kinds of oughts without understanding both. In particular, if you try to do everything with ought-to-do’s:

    • One would fall into a kind of Cartesianism: we’d need to think of linguistic episodes as essentially the sort of thing brought about by an agent whose conceptualizing is not linguistic.
    • We’d be precluded from explaining what it means to have concepts in terms of the rules of the language. Ought to do’s have the form of “in circumstances , do ” - what language are and stated in? Regress of rules without ought-to-be’s.
  • This is important because natural way to think of rules is exlusively in terms of Ought to Do (Sellars himself advocated this earlier: “A rule is always a rule for doing something”).

  • There is also an analogous distinction involving permission, rather than obligation.


This lets us avoid the rule obeying regress.

This distinction also can be used to avoid paradoxes of “ought” for things we don’t have control over, e.g. I ought to believe such-and-such but I do not have control over my beliefs. Only ought-to-do’s presuppose that one has agency to conform, while ought-to-be’s do not.1


  1. Ought to believe