In existential guilt, the guilt that has been invoked may be due to the comparison of self to others. Such comparison could be explained with the social comparison theory  – it is when we learn our attitudes and abilities by comparing ourselves to others. Since there isn’t an objective standard to define pro-environmental behaviour, people make use of others as a standard measure to measure themselves. The comparison made towards others is expressed in two different ways – upward social comparison and downward social comparison.

Upward social comparison is when we compare ourselves to people who are better than us in relation to a trait or ability. In the context of the environment, an individual may feel a sense of guilt when others produce a smaller carbon footprint daily, as compared to one.

Downward social comparison is when we compare ourselves to people who are worse than us in relation to a trait or ability. In order to boost one’s ego, an individual who uses a single-use plastic cup once a week may feel good by comparing to someone who uses a single-use plastic cup once a day.

Engaging in comparison may also influence how one thinks – people may adopt other’s people’s view and it can be express in their behaviour. The process is known as social tuning.