The Journal of Personality and Social Psychology reports that conservatives are more likely to be strict about classify geometric shapes than liberals are.
From Mental Floss:
In three different experiments, researchers asked people to differentiate between perfect and imperfect shapes. The study subjects also filled out questionnaires regarding their political beliefs and their sense of moral outrage over groups of people who deviate from social norms or rules.
They found that the more conservative views a person endorsed, the more likely they were to differentiate between perfect shapes and their ambiguously imperfect counterparts — like a triangle that’s just a little rounded or a slightly wobbly circle. In other words, conservatives were more sensitive to deviance from the visual standard, just as they might be more sensitive to deviance from social norms.