Give not that which is holy unto the dogs, neither cast ye your pearls before swine. (Matthew 7:06)
He's tried to tell journalists about economics.
This Herculean effort hit trouble when he told them it was irrational to vote, because the costs (the walk to the polling booth) outweighed the benefits (the chance that your vote would be decisive):
The journalists reacted to my claim with a mixture of outrage and laughter. They couldn't decide on whether I was a monster or simply a fool.
The problem here, I suspect, is simple. Russell was thinking, as economists invariably do, only in terms of instrumental rationality. But this is only one type of rationality.
A story by John Searle (The Construction of Social Reality p137-8) illustrates the point. Instrumental rationality - the economists' way of thinking - tells us that if we value two things, there must be some odds at which you would exchange the two. There are some odds at which we we happily pay $1 for the chance of winning a sports car.
Sounds logical? It's not, says Searle. There are no odds - not even billions to one - that would induce him to accept a penny in exchange for a risk to his son's life.
This is because to accept such odds would merely raise the question: what kind of father are you? In this context, Searle rejects instrumental rationality in favour of symbolic rationality. That is, he acts so as to symbolize or signal the kind of person he is.
Now, I suspect voting is (traditionally) symbolically rational. People vote not out of cost-benefit considerations but to symbolize who they are. My grandad voted Labour all his life simply because that was what working-class people like him did. He no more thought of voting Tory than he thought of leaving the house without his hat - it was just against nature to do so.
This, I suspect, is why voter turnout has fallen is the UK. The symbolic rationality motive for doing so has declined, partly because class allegiances have weakened, and the instrumental rationality motive is just too weak to replace it.
For more about the manifold nature of rationality, can I recommend two great books? There's Robert Nozick's The Nature of Rationality - a far better book than that other one - and Alasdair MacIntyre's Whose Justice? Which Rationality?
These should challenge economists' preconception that rationality is a straightforward concept.