An evolving thesis of mine, pulling on research from fellow bloggers Bryan Caplan and Robin Hanson among others, is that a more complete theory of public choice has got to be a theory of public moral sentiment.

When voters vote the likelihood that they will swing the election is so low that it doesn’t make sense to vote in a narrowly self-seeking way. If all you cared about was your own personal interest it would be best not to vote at all.

So, given that a voter votes he or she is likely voting on the basis of something else. My working theory at this point – hat tip to Andrew Gellman – is that voters have moral preferences over all of humanity and perhaps all of nature itself.

Moral preferences are relatively weak in comparison to narrow self-interest but they are extremely broad. That is we don’t care as strongly about the right thing happening as we do about good things happening to us and our loved ones, but we care about the right thing happening in a huge number of cases that have virtually nothing to do with us or our loved ones.

In the voting booth, however, people are presented with a unique opportunity. Here their choice has a very low likelihood of making a difference but it potentially makes a very broad difference.  This is where we should see weak but broad moral preferences completely swamp strong but narrow self-interest.

Thus we should expect votes to be more dependent on what people think is morally right than on what people think is in their best interest.

I had picked up from the work of John Haidt that Conservatives and Liberals have different moral foundations. I assumed that this was largely due to a combination of genetics and peer influences.

However, Will Wilkinson points out some research that shows specific cuing effects can turn up or turn down the foundations of Conservative and Liberal morality.

Wright and Baril argue, drawing on an array of evidence that conservatives are more averse to threat, instability, and uncertainty, that a sense of threat tends to activate the binding foundations, producing more conservative moralities. In the absence of a sense of threat, or when exhausted from the effort of keeping our conservative moral emotions inflamed, we default to the relatively effortless liberal, individualizing foundations.

What it sounds to me Wright and Baril are saying is that the liberal setting is the one we tend toward when our defenses are down. That is, liberal morality is the morality of comfortable security.

What makes this interesting is that liberal voting tends to increase economic security. For better or worse one of the consequences of redistribution is to limit the variance in economic outcomes. This should give more people a sense of security, which would in turn shift more folks towards the liberal axis.

It all depends on the strength of various effects but what you could get is a self-reinforcing liberalism. Something happens – maybe a rapid rise in productivity – that makes people feel more secure. The security makes their moral sentiments more liberal. More liberal moral sentiments lead them to vote for redistributionist policies. Redistributionist policies increase the sense of economic security further strengthening the liberal voting trend.

I am thinking in terms of liberalism here because it seems to be growing in strength over time, which is of course consistent with rising economic security from technological progress.

However, the self-reinforcing nature produces the possibility for multiple equlibria and the notion that a single event could kick a nation from one level of liberalism to another.