In reality there are an unknown number of variables that should impact your decision-making in this regard.

How competent a swimmer are you? What is your current mental and physical state? Do you know the young girl? How many family members do you have that are directly reliant upon you for survival? Do you think that you could realistically save her? Even if you could, is it your moral duty to risk yourself for her sake? Whose life is worth more, and is it possible to even work that out?

There is no right answer here, you could argue for either course of action with equal vigour.

The problem is that society expects self-sacrifice in the service of others, particularly for close friends and especially for family. When it comes to friends or family members who are sick (physically or mentally), it is automatically presumed that we ‘should’ and ‘must’ help them as much as possible. It seems noble and heroic to sacrifice one’s self in the service of others. Society seems to value and idolise those of us who give everything in the support of others.

“You are doing God’s work”, ‘You are a Saint’, ‘If more people were like you…’

I don’t agree with this line of reasoning. I don’t think that anybody (unless it is a requirement of the line of work that they have freely chosen to perform) should completely sacrifice themselves when helping others.

People should look after themselves first. Now this is not a selfish idea either mind you, I believe that it is to the benefit of society as a whole, as well as in the best interests of the individual that would be the recipient of the sacrifice. Because if you don’t look after yourself, and you fall, how will that person get the help they need?