At Desert Landscapes Uriah describes a conversation that could easily exist:
Singer: “dancer, you should really give 30% of your income to famine relief.”
Dancer: “but you don’t.”
Singer: “all the same, one should.”
Dancer: “but you don’t!”
Technically, Dancer’s position isn’t very sound because the ethical value of donating to famine is unconnected to whether Singer does it. Singer’s comment is true or false regardless of what Singer does; thus, Dancer can’t object to donations simply because Singer doesn’t bother.
As Uriah notes, however, there is something else going on here because most people will intuitively think that Dancer’s position is valid and does have merit:
What do Dancer’s comebacks presuppose? One thing they presuppose is the *universalizability* of ought statements. If Dancer ought to Z in circumstances C, then Singer ought to as well. ... The other thing Dancer presupposes is something like this. Given that Singer is not inclined to give her money to famine relief, she does not genuinely believe that she ought to, profess what she will. More generally, if x is not inclined to Z, then x does not have a genuine belief that x ought to Z. Or contrapositively, if x genuinely believes that x ought to Z, then x is inclined (motivated) to Z. This latter principle is a kind of internalism – we may call it, following Darwall, “judgment internalism,” or perhaps more specifically, “first-person judgment internalism” (to signal that it’s applied only to first-person moral judgments).
If the principles of FPJI and universalizability hold, then Dancer’s comebacks indeed make sense. “Dancer ought to give 30% of her income to famine relief” entails (by universalizability) “anyone in Dancer’s circumstance ought to give 30% of their income to famine relief.” With the aid of “Singer is in Dancer’s circumstance,” this entails “Singer ought to give 30% of her income to famine relief,” which in turn entails (by FPJI) “Singer is inclined/motivated to Z.” When Dancer notices that this last statement is false, she employs (implicitly) a sequence of modus tollenses (if that’s a word) to reach the conclusion that the original statement (that she herself ought to give 30% of her income to famine relief) is false as well. So FPJI is implicit in everyday discourse.
The obvious question is: are we justified in reasoning backwards, using the falsehood of the conclusion to believe that the original premise is false as well? I’m not so sure. First, the conclusion may not be false. Singer may be motivated to donate money but doesn’t because she donates money to other causes (that, however, would mean that the circumstances weren’t identical, so while this may be a fair objection in real life, it may not be fair here). Second, Singer may be motivated to donate money but may have another, stronger motivation not to. It might be reasonable for her to suggest that Dancer should donate her money on the theory that Dancer lacks this counter-motivation.
Such comments aside, though, Uriah’s argument here is very interesting and may reveal one reason why we recoil from hypocrites.
If a person promotes something good which we agree with (say, feeding the hungry) but doesn’t do it, then we may be (implicitly) concluding (along the lines Uriah describes) that this person not only doesn’t really believe it but, in fact, is staking out the position that the action is wrong. Just as the Uriah’s line of reasoning leads to “the original statement (that she herself ought to give 30% of her income to famine relief) is false,” the line of reasoning here leads to “the original statement that we should feed the hungry is false.”
If you strongly believe that we should feed the hungry, you’ll recoil from that — whether it is stated outright or merely implied by hypocrisy. A person who doesn’t feed the hungry but who also says nothing about the issue doesn’t bother us in the same way, I think, because they don’t seem to be staking out a position that feeding the hungry is wrong. The fact that they don’t might be something we would criticize, but it’s not at the same level as the other person.