Mr Anton Casey may have crossed the line of acceptable social conduct but the netizens baying for his blood may be exhibiting the same kind of ungracious behaviour ("Expat apologises for 'poor' remarks about commuters"; last Wednesday).
In the past decade, psychologists have realised that the tendency to harbour prejudices towards others whom we fail to relate to is universal.
They can range from members of the opposite sex, members of different ethnic groups and people with disabilities to social, sexual and religious minorities.
Some people have been found to be more prone to this kind of behaviour: those with narcissistic traits and those with a strong sense of their own elevated position in a social or professional hierarchy. These subconscious prejudices can affect how we think of and behave towards others.
Humans have a deeply ingrained need to feel that they belong to a group, with both positive and negative consequences.
This tendency to segregate ourselves into "us" and "them" can easily be manifested.
British social psychologist Henri Tajfel and his colleagues found that simply assigning people randomly to two teams was sufficient to produce a measurable preference for members of their own team.
The fact that we effortlessly associate with an "inside" or "outside" group may explain why the growth of social media - and hence a wider social network - has increased new social boundaries.
Posting bullying or abusive comments anonymously on social media as an "in" group against an outsider is one insidious result.
Paradoxically, engaging in social ostracism or bullying can also leave us feeling dehumanised.
A group of undergraduates at the University of Queensland were asked to think of a time they had ostracised someone socially, and then rate their own moral behaviour with reference to traits such as open-mindedness, rationality and self-restraint.
The students rated themselves as less moral if they had behaved immorally against another person, and are more likely to act socially afterwards in an attempt at atonement.
Society can help remove the boundaries between antagonistic groups by highlighting our shared aspirations, values and humanity.
Putting people of different persuasions - such as ethnic or religious groups - in a team can help foster bonds and mutual understanding.
Even if there is a tendency for us to denigrate others of a different group, if we salvage it by acts of atonement, then perhaps all is not lost.
Maria Loh Mun Foong (Ms)
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