The Argument from Hypocrisy (a close cousin of the “demandingness objection“) is one of the strongest objections to utilitarianism.  (Strangely omitted from Scott’s inventory).  The argument has two steps.

Step 1. Note that utilitarianism implies extreme moral demands.  For example, maximizing total happiness requires you to give away all your surplus wealth to the needy – at least needy people whose behavior is unlikely to respond much to incentives, such as children.

Step 2. Point out that even the staunchest utilitarians are light-years away from fulfilling these extreme moral demands.  Even Peter Singer “only” gives 20%.

To put the Argument from Hypocrisy conversationally: “Your view implies that you should give away all your surplus wealth to needy kids.  But you don’t.  If even explicit utilitarians like you don’t seem to take their views seriously, why should anyone else?”

To be fair, there is an obvious though embarrassing reply to Argument from Hypocrisy.  Namely: “Like most humans, I’m deeply morally flawed.  I know utilitarianism is true, but I’m too weak to live by it.  Saint Paul had it right: ‘For the good that I would I do not: but the evil which I would not, that I do.'”

On reflection, however, a variation on the Argument from Hypocrisy is largely immune to the Pauline reply.  I call it the Argument from Conscience. 

Instead of harping on utilitarians’ moral weakness, the Argument from Conscience begins by singling out the most morally exemplary utilitarians. 

Take Bill Dickens.  I’ve known Bill for almost a quarter-century.  In all these years, I have repeatedly witnessed him spontaneously take unpleasant actions out of a sense of moral duty.  I have never witnessed him treat another person badly.  Ever. 

While Bill Dickens is a man of conscience, he’s also officially a utilitarian or near-utilitarian.  How could his extreme scrupulousness possibly discredit his utilitarian philosophy?  Simple.  Like every other utilitarian, his behavior is wildly at odds with utilitarianism’s demands. 

Although Bill gives generously to charity, he consumes far more than he needs to keep working.  He skis in Colorado.  He goes to GenCon.  Bill also clearly prioritizes his contractual obligations above the desperate need of total strangers – even when repeated play is unimportant.  If Bill forgot to tip a waiter, he would strive to make amends to the aggrieved waiter – not mail the waiter’s tip to Oxfam.

The upshot: If Bill Dickens told me, “Like most humans, I’m deeply morally flawed.  I know utilitarianism is true, but I’m too weak to live by it,” I wouldn’t believe him.  Bill is a paragon of decency.  If he really believed he morally owed vast sums to the poor, he’d skip GenCon and fork over the money.  Since he doesn’t, I infer that despite his official position, utilitarianism seems almost as crazy to him as it does to me.  The same goes for every earnest yet non-compliant utilitarian.  Utilitarianism doesn’t just go against their interests.  It goes against their consciences.

To put the Argument from Conscience conversationally: “You live by your conscience.  If you really thought utilitarianism was true, you would live up to it.  Yet you don’t.  If even scrupulous utilitarians like you don’t take the view
seriously, why should anyone else?”

And that, my utilitarian friends, is the Argument from Conscience.  The problem isn’t that your doctrine is too good for you.  The problem is that you’re too good for your doctrine.