Stella O'Malley: 'If we are to be civilised, decent people, we need to be willing to stand up to evil'
What do you do? You're on the Luas and one man attacks another, punching him and kicking him in the head.
Neither men fight like boxers and neither is particularly big and burly. But then the victim pulls a knife and the assailant goes completely mad and starts to repeatedly stamp on his head; almost killing him in the process.
So, the question is, do you quickly stand back and film the fight? Or do you silently watch the whole thing? Because that's what lots of people did.
Or do you get the hell off the Luas as fast as you can? Because that's what pretty much everyone else did.
Only one man tried to intervene in this public mauling.
As our population grows, the frequency of incidents like this may increase.
In China, the death of two-year-old Yueyue in 2011 sparked outrage and launched an online campaign that hoped to address moral apathy.
Little Yueyue's mother was distracted by doing the laundry when the child escaped out of the house and toddled across the road. A hit-and-run driver knocked her down but then Yueyue's plight was ignored by 18 bystanders who walked on by as she lay dying on the road.
We know this because there is CCTV footage of these adults walking past the little girl. Then another vehicle drove over her and, finally, a migrant worker who was collecting rubbish goes to her aid but it is too late.
Afterwards many analysts decried the apparent moral decay of a large urban population and this incident also inspired a campaign to 'Stop Apathy' in a bid to encourage bystanders to respond appropriately when they see others in difficulty.
Perhaps we need a similar campaign in Ireland because, as we move from a rural population to an urban population, there seems to be a growing sense of alienation from other people's troubles.
No longer do we quickly intervene at the first sign of any trouble because of the justifiable fear that the attacker might turn on us.
However, moral reasoning is what separates man from beasts and if a man is being violently attacked before our very eyes, it is our role to respond appropriately.
Someone could have rang gardaí.
The crowd who watched the fight could have supported the man who tried to intervene.
In any given situation it is the crowd who hold the power - even though they don't know it. There is power in numbers and, in any given situation, the bystanders have all the power; individuals are only powerful for as long as the bystanders comply.
If we are to be civilised, decent people, we need to be willing to stand up to evil. Yes, it is hard and yes, it is easier to look away and feel powerless in the face of evil.
It is easier not to speak; not to act. But the mark of a good person is the person who finds the strength within them to make the world a better place as they go about their daily life.
In some contexts, this might mean ringing gardaí because it is too dangerous to do anything else.
In another context it might mean pressing the bell "in case of emergency" while in others, if you are particularly brave or if you are experienced at speaking to emotional people, you could try speaking to the violent person. Some people are good at speaking empathically, making eye contact, appealing to the person's better nature and slowing the whole thing down so the attacker can start to use the more intelligent side of their brain instead of remaining in the madness of their emotional brain.
The reason why many of us react strangely in dangerous situations is because of the amygdala - an almond-shape set of neurons located deep in the brain which plays a key role in the processing of emotions.
When the amygdala gets triggered, this unleashes instinctive reactions in each person. So some people instinctively fly for cover, others immediately turn and fight, while other people just freeze in the face of danger.
But this instinct in the brain is the more animalistic, behavioural side of our psyche. The more civilised, humane response comes a few moments after our instinctive response, and this is the better part of us.
The more we can move beyond our instinctive response to a more rational response, the more we are connected to our finer minds.
Remaining in your animalistic, instinctive response is easier for the brain while trying to be a force for good is hard work.
But that's what makes us human; it's just not good enough to act as an animal would, we need to be a bit better than that.