In large democratic elections, the selfish individual will not vote because the costs of voting are positive and significant, but the probability that one vote will alter the outcome of the election is vanishingly small. Thus the personal gain from voting is vanishingly small. The cost, however, is a significant amount of time and energy that could have been devoted to other, materially rewarding, purposes. It follows also that a selfish individual will generally not bother to form opinions on political issues, because these opinions cannot affect the outcome of elections. Yet people do vote, and many do expend time and energy in forming political opinions. This behavior does not conform to the selfish gene model.Here are three factors which contribute to pro-voting behaviour:
- Forming political opinions is not "about" voting - it is about signalling. It signalls affiliation with powerful individuals, becoming part of a powerful tribe and showing that you care about issues facing society. So: people form political opinions for signalling reasons, not to decide which way to vote. People typically do not like to admit all this to themselves - because it makes them look bad. So: they use a cover story - for others and themselves: their political opinions are about policy. This makes them seem more noble - but it makes not voting into inconsistent behaviour that might give away their motives - so they vote.
- Your decision whether to vote has more impact than changing just one vote. That's because there are other people out there, similar to you, making the same decision. Imagine that you decide deterministically, and they are exactly like you. Then they will decide as you do. In those cirumstances your vote carries the weight on t heir numbers. In practice, others may not be exactly the same as you - but the principle still holds. This idea uses "anthropic" reasoning - and it is not new.
- Voting may be (partly) an evolutionary legacy. Voting makes sense - in hunter gatherer tribes. The human brain mostly acts as though it is in a hunter gatherer tribe. This might explain some pro-voting tendencies.
Summary: people don't vote in national elections in order to influence the results. Rather voting is part of a behaviour pattern to do with affiliating with powerful individuals, being part of a team, and being involved in big and important moral and political issues. It is in the interests of politicians to manipulate their supporters into voting. The human brain is malleable - so sometimes they succeed.