Thursday, April 14, 2011

Moral and conditional realism

  1. (Premise) I know that if I am human, I am mortal.
  2. (Premise) If I know something, it's true.
  3. So, it is true that if I am human, I am mortal.
  4. (Premise) If something is true, it has truth value.
  5. So, that if I am human, I am mortal has truth value.
  6. (Premise) That if I am human, I am mortal is a conditional.
  7. So, some conditionals have truth value.
Continuing:
  1. (Premise) I know that it is wrong to torture the innocent for fun.
  2. So, it is true that it is wrong to torture the innocent for fun.
  3. So, that it is wrong to torture the innocent for fun has truth value.
  4. (Premise) That it is wrong to torture the innocent for fun is a moral claim.
  5. So, some moral claims have truth value.
Another argument:
  1. (Premise) No one is morally to blame for violating a moral rule that no one could know.
  2. (Premise) One is only to blame for violating a moral rule.
  3. (Premise) Someone is to blame for something.
  4. So, someone is to blame for violating a moral rule.
  5. So, some moral rule can be known.
  6. (Premise) Necessarily, only truths are known.
  7. So, some moral rule can be true.
  8. (Premise) Necessarily, anything that is true has truth value.
  9. So, some moral rule can have truth value.
This is, of course, a problem for non-realist accounts of conditionals and morals.

5 comments:

Jonathan Livengood said...

I suppose I accept premiss (2), but I have no idea how to go about justifying it. Do you think something can be said in its favor or is it a take-it-or-leave-it starting point?

Alexander R Pruss said...

Well, there is an argument from authority. In all the discussion of Gettier problems and the old justified-true-belief story about knowledge, the claim that truth is required for knowledge seems to be the least controversial.

Dante said...
This comment has been removed by the author.
Mike Almeida said...

I'm not sure what non-realist accounts of conditionals are (do you have in mind assertion conditions rather than truth conditions?). But this is a problem for non-realist accounts of morality only if you mean by 'realism' that moral judgments take a truth-value. But that is an extremely weak form of realism. Subjectivist accounts of morality admit that moral judgments take a truth-value.

Alexander R Pruss said...

Right: the kind of realism I have in mind here is just the having truth values kind.