Is the 'lesser of two evils' an ethical choice for voters?

Every election cycle, there are citizens who don't like either of the candidates nominated by the two major political parties.

And so, a familiar debate begins: Is a vote for a third party a principled stand — or wasteful naiveté?

This year, party discord has swelled the numbers of dissatisfied citizens, and the debate is even louder than usual.

Donald Trump and Hillary Clinton are unprecedentedly unpopular. On the left, intense pressure is mounting to vote for Clinton to avoid what many think will be genuine, large-scale dangers of a Trump presidency. This pressure is most intense in states that rank relatively high on what Nate Silver describes as the "voter power index," like Nevada or Florida. But such arguments are also engendering a defiant backlash as voters declare, "I won't vote … out of fear."

As a moral philosopher, I'm particularly interested in the question of whether we can be obligated to vote for someone we dislike. Let's look at the arguments.

Pretend for a moment that you are a swing-state voter who agrees with the following four statements.

• A Donald Trump presidency would be a disaster.

• A third-party candidate would be better still.

• Neither third-party candidate has a serious chance of becoming president.

My point here is not to defend these claims, since it doesn't matter whether I believe them. What matters is that there are people who do accept them, and they are trying to decide whether they really ought — whether they are morally required — to vote for Clinton.

Although many such voters are predictably Bernie Sanders supporters who object to Clinton on various grounds, the dilemma applies to many on the right as well.

Trump has divided the Republican Party, and many conservative voters — or even conservative leaders — have had trouble supporting the nominee. It is quite possible that these individuals also endorse claims 1-4.

One of the things that Green Party supporters say is that you aren't supposed to vote for the lesser of two evils — after all, the lesser of two evils is still evil. Rather, you're supposed to vote for the best candidate.

One way to think about the third-party vote is that it is a form of conscientious objection. Such a vote, like abstaining from voting, allows the voter to avoid acting in a way that she thinks is wrong or distasteful. We can understand this person's vote for a third party as a commitment not to let the badness of the world force her into violating her principles.

The issue being identified here is not a new one. Philosophers have long argued that, while the consequences of one's actions are morally relevant, they rarely or never amount to a requirement to act in a way inconsistent with one's firmly held commitments. A British philosopher named Bernard Williams famously argued that if we were forced to abandon our ideals every time the world conspired to make following through with them suboptimal, this would rob us of our integrity. This is a very compelling idea.

Williams seems right that we are not always obligated to violate our own principles or commitments in order to promote the greater good. But surely this idea has limits.

For, as critics of Williams have often said: When the consequences of one's action or inaction get bad enough, following through for the sake of keeping one's hands clean starts to seem self-indulgent. Indeed, even Williams admitted that you may sometimes be required to violate your principles for the greater good.

If, for instance, a vegan lifestyle were central to my self-identity and I found myself in a situation where my abstaining from eating meat would hurt my host's feelings, plausibly I would be allowed to respectfully turn down the food. If, however, either the moral costs of turning down the food were much higher — for instance, if I were a peace ambassador to a foreign government host with thin skin and a finger on the nuclear launch button — or I was only toying with the idea of veganism, then my preferences would not play the same justificatory role.

For those who endorse claims 1-4, it's likely the case that the costs of not voting for Clinton are quite high, and that voting "for the best candidate" is not really such a deep commitment.

On the first point: If a Trump presidency would be as bad as predicted by claim 1, then failing to vote for the candidate who can stop him is contributing to what will likely be a massive, moral harm. While it's true that each of us has but one vote to cast, in so casting it, we are participating in a collective action with serious moral consequences, and that makes our actions morally serious.

On the second point: Although voting for a candidate we dislike can feel dirty, my guess is that most of us don't actually hold the ideal of voting for the very best candidate as a central, guiding commitment. Rather, we see voting as a thing we do, but not something that's deeply tied to who we are. So voting in a way that feels dirty does not seem to rise to the level of undermining our integrity.

Those who are wrestling with whether to vote for Clinton out of fear of Trump are tapping into something real, then. They are distressed that a threat of bad consequences can undermine their freedom to choose as they please. But it is self-indulgent, I would argue, to claim their integrity is on the line. If you believe Trump is a moral disaster, then you may well be obligated to vote for Clinton — even if that means getting your hands a little dirty.