Why People With the Same Big Five Profile Vote Different Ways

Every few election cycles, a viral article claims that personality predicts politics. People with high Openness vote left, people with high Conscientiousness vote right, and the rest is detail. The claim is half-true, which is the most dangerous kind. The data is real but smaller than the headlines suggest, and the things that actually predict how someone votes have almost nothing to do with their Big Five score.

The trait link, briefly

There is a real, replicated link between Big Five traits and political ideology. The two clearest patterns:

Higher Openness correlates with more liberal or left-leaning attitudes, particularly on cultural issues — immigration, traditional values, social change. The effect shows up across many countries and surveys ¹.

Higher Conscientiousness correlates, more weakly, with more conservative or right-leaning attitudes, particularly on economic and order-related issues. The effect is smaller and less consistent across countries than the Openness effect.

The other three traits show even smaller, less reliable effects. Agreeableness has a small positive link with progressive social attitudes. Neuroticism and Extraversion show mixed effects depending on the specific issue.

So far, this fits the viral story. But the size of these effects is the part that the viral story usually leaves out.

How big is "real"

The correlations between Big Five traits and ideology are usually in the range of 0.1 to 0.2. In plain English, that means knowing someone's trait score gives you a small edge over chance in guessing their politics — but not a big one.

For comparison, knowing a person's parents' political affiliation, where they grew up, their religion, or their education level each give you a much larger edge than their Big Five score does ¹. Personality is one of many predictors, and it is not the biggest one.

This is why a room full of high-Openness people can include socialists, libertarians, centrists, and people who do not vote at all. The trait is a small loading on top of much larger forces.

What actually predicts how someone votes

If you wanted to build the best possible predictor of someone's vote and could pick five variables, personality would not be in your top three. The variables that do most of the work:

• Parents' political affiliation. The single biggest predictor across most democracies. Most people's political home looks a lot like the one they grew up in.
• Region. Where someone lives — and where they grew up — predicts ideology strongly, partly through culture and partly through self-selection.
• Religion and religiosity. Religious tradition and frequency of practice both predict ideology, often more strongly than any personality trait.
• Education level. Particularly the difference between college and non-college, which has become one of the strongest predictors in many countries in the last 15 years.
• Income and economic class. A predictor, though less reliable than the others and changing over time.

Personality enters this list well below the top five, and its effect is partly mediated by these other variables — for instance, high-Openness people are more likely to move to cities and pursue more education, both of which independently predict more liberal politics.

Why the trait link exists at all

The most careful work on why Big Five traits link to politics at all comes from researchers who study what is called negativity bias — the degree to which people pay more attention to negative or threatening stimuli than to positive ones.

The Hibbing, Smith, and Alford framework argues that political ideology partly tracks how strongly someone responds to threat. People with stronger threat responses tend to prefer more order, more stability, and more in-group protection. People with weaker threat responses tend to prefer more openness to change and less protective structure ².

This framework explains the personality link mechanically. Higher Openness often comes with weaker threat responses to novelty. Higher Conscientiousness often comes with a stronger preference for order. The traits and the political attitudes are partly two readings of the same underlying disposition.

It also explains why the trait link is small: most political opinions are not pure threat responses. They are bundles of identity, group belonging, economic interest, and learned positions — and the threat-response loading is one ingredient among many.

The case of the two openness siblings

A useful thought experiment. Take two siblings raised in the same conservative religious household, both scoring identically high on Openness, both equally curious and unconventional.

One of them might leave the religion at 19, move to a liberal city, and end up firmly on the political left. The other might stay in the religion, channel their Openness into theology and arts within it, and end up firmly on the political right.

Same trait. Different politics. The reason is that the trait did not vote. The trait shaped how the person interacted with their environment, and the environments were different.

This is what the data picks up. Across populations, high-Openness people lean slightly left on average — because, on average, they sort into environments that pull them that way. Within any one person, the trait is only a nudge.

What this means for using personality data

Three honest things.

Do not predict someone's politics from their personality. If a Big Five report describes someone as high Openness and you assume their politics, you will be wrong about 30 to 40 percent of the time. That is a high error rate for a low-value prediction.

Do not over-explain political disagreement through personality. The popular framing of "left and right are different personality types" is overstated. Most political disagreement runs through shared traits and different interpretations of fact, history, and interest. Treating it as a personality difference flattens what is actually going on.

The trait link is most useful for understanding stability, not direction. Personality traits are fairly stable. Political opinions, at the individual level, are less stable than people think — they shift with life events, generational pressure, and information environment. The trait may help explain why someone is uncomfortable with rapid change or with strict order. It will not tell you which party they will vote for.

Why this matters more than it seems

A growing share of cultural conflict gets explained, in op-eds and on social media, as a fight between personality types. "The conscientious vs the open." "The agreeable vs the disagreeable." The framing is sticky because it implies the disagreement is permanent and almost biological.

The data does not support that framing. Personality contributes a small amount to political variance. Most of the variance comes from things that are not personality: family, region, religion, education, interest, generation, and information.

Treating political disagreement as a personality difference makes it feel hopeless. Treating it as a learned bundle of positions on top of a small dispositional loading makes it tractable. The data points at the second reading.

If you take a Big Five test and the report talks about your politics with any confidence, that is the report exceeding what the science supports. The trait is one ingredient. It is not the recipe.

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