Is voting a rational process? If so, the ordinary voter would have subjected his decision to a huge amount of analysis. Which party do the candidates belong to? What were the promises of the ruling party when it came to power in 2014? What percentage of those promises were fulfilled? Do they have valid reasons for not delivering on what they had promised? Which party has a higher chance of delivering on future promises? All of this would be based on lots of number crunching. One will have to take a look at gross domestic product growth, fiscal numbers, inflation, employment generation, etc. It is quite doubtful that even an educated voter will indulge in such detailed analysis before casting his or her vote. If voting is not based on any rational analysis, what do the vast majority of our voters, many of them not even literate, base their choice on?

In earlier days, impacting election results in India through poll-booth capturing was very common. Thanks to the secret ballot and robust security arrangements, it is believed that most elections now are fair and are not manipulated. But the truth is that manipulation still continues. Today, politicians manipulate the electoral process by influencing voters much before they have entered the polling booth. Political parties use a sophisticated understanding of human behaviour and sub-conscious preferences to achieve this manipulation.

On the surface, voting looks like an individual act, where each person votes according to his personal likes and dislikes. But according to Jonathan Haidt, a social psychologist and the author of the book The Righteous Mind: Why Good People Are Divided By Politics And Religion, voters don’t always vote for self-interest (that is, for candidates and policies that would bring us, as individuals, the greatest benefit). Rather, they tend to vote for their own group’s interest. Voting is more of a group behaviour.

Henri Tajfel, a social psychologist, introduced the concept of social identity—people’s sense of who they are. This identity draws upon their notions of belonging to a relevant social group. Tajfel contended that in order to increase our self-image, we enhance the status of the group to which we belong. We can also enhance our self-image by discriminating and holding prejudiced views against an “out-group" (one that we don’t belong to). In doing so, we tend to exaggerate the differences between groups and the similarities of those within the same group.

Since early evolutionary times, humans have always had an inherent tendency to form in-groups that are willing to cooperate and also fight another group. In olden days, one’s tribe was the only in-group one had. Today, some of the strongest factors for in-group formation are religion, caste, race and language. In most countries, discussions on social issues—especially so among conservative groups—are strictly along these lines.

According to Gordon W. Allport, an American psychologist and author of the book, The Nature Of Prejudice, religion is one of the most significant factors in most people’s philosophy of life. Religion usually stands for more than faith—it is the pivot of the cultural traditions of a group. In its institutional organization, religion is divisive. So, it is not surprising that in many parts of the world, religion and religious beliefs do play a significant role in affecting one’s voting behaviour. In India, a very important social identity marker is one’s caste. In some cases, caste identity might even be more significant than the religion one follows.

Politicians have intuitively understood the core of this social identity theory very well. It all begins with the selection of an election candidate. Political parties will do a minute analysis of each constituency to understand the size of each religious and caste group in that geographical unit. Most political parties will select a candidate who belongs to one of the largest religious or caste group in that constituency. Politicians have an ability to construct the narrative of a complex issue to narrowly focus only on an issue that either divides people or brings them together. This election has witnessed a bigger tendency to indulge in polarization than ever before.

Whenever there is polarization along these identity lines, even the most rational person finds it very difficult to take a stand that is considered favourable to the other side. We rarely break ranks and vote against our group interests. For when we do, we risk appearing disloyal to our peers and our communities.

An air of polarization allows voters to conveniently forget the political mistakes of those they support. According to a study by Elizabeth Phelps at New York University, an act of terrorism committed by a member of the in-group may be forgotten faster than a similarly reprehensible act perpetrated by a member of a foreign group. We also tend to construct truth to fit into our beliefs about our in-group. Steven Pinker, the famous evolutionary psychologist, said that one function of the mind may be to hold beliefs that bring the belief-holder the largest possible number of allies, protectors or disciples, rather than beliefs that are more likely to be true.

Political scientists often distinguish between “instrumental voting" and “expressive voting". Instrumental voters use their votes in order to influence outcomes. Expressive voters, however, don’t care about the outcome, but instead derive “expressive" value from the act of voting. Expressive voting is seen as providing a psychological reward, like getting to “affirm one’s identity" or “feel a sense of belonging". A lot of voting today in India is expressive voting that emanates from deep evolutionary fears fanned by politicians.

Biju Dominic is chief executive officer of Final Mile Consulting, a behaviour architecture firm.