COURAGE is a virtue and heroism is admirable, but do we have a right to demand them? Which of us cannot look back on his or her own life and remember decisions, or compromises made, or silences kept because of cowardice, even when the penalties for courage were negligible?
If we are cowardly in small things, shall we be brave in large? Have we the right to point the finger until we have been tested ourselves? When we read of the seemingly lamentable conduct of the captain of the Costa Concordia, Francesco Schettino, who left his passengers to their fate, do we say, ''There but for the grace of God go I''?
I have witnessed some very fine instances of bravery. Once, as a junior doctor, I was walking through the hospital grounds when I noticed a patient sitting on a bench slashing his wrists with a broken bottle of vodka whose contents he had just drunk. I asked him to come into the hospital where I could sew him up (sobering him up was beyond my powers). He climbed up the fire escape and clambered over the railings on to a narrow ledge, on which he was swaying drunkenly. A porter and I went up the fire escape: the man threatened to jump if we came nearer.
We decided we had to make a grab for him; as we did so, he jumped. We held him suspended by his arms three storeys up. First he shouted, ''Let me go, you bastards!'' and then, ''Help, I'm falling!'' - a metaphor for the whole of human life, when you come to think of it.
By the luckiest chance, two policemen arrived at the hospital and rushed up the fire escape to our assistance. Without a moment's hesitation, they climbed on to the ledge themselves and hauled the man to safety. They brushed away my commendation, and even my thanks; in their own opinion, they had only done their duty, what they were expected, and expected themselves, to do.
I witnessed another instance of great bravery many years later, when times were changed. It was in the prison in which I worked as a doctor. A prisoner set fire to his mattress in his cell, and years of research by the British Home Office seemed to have gone into disproving the old saying that there is no smoke without fire, for the mattress produced the thickest, most acrid, black smoke that I have ever encountered, without much in the way of flame.
With no thought for his own safety, a prison officer entered the cell and pulled the prisoner to safety. As I sent the officer to hospital to be treated for possible smoke inhalation, I praised him highly and said I expected he would receive an official commendation.
He smiled pityingly at my naivety and said: ''A reprimand more likely.'' And so it proved: he had not followed procedure, which was to leave it for the fire brigade.
A world in which a man can be reprimanded for bravely saving another's life is not propitious for the widespread practice of bravery. Virtues tend to disappear in the dissolving acid of rationality.
What might Captain Schettino say in his defence? Let us, for the sake of argument, leave aside the possibility that the whole disaster was an error of his seamanship, and suppose instead that it was what some people call ''one of those things''.
In a world used to the utilitarian Zeitgeist, he might say that if he had stayed on board and gone down with his ship, nobody who died would have been spared. We imagine a captain on his deck, as he slips under the waves, but this is quixotic romanticism if in fact no one is saved.
Can we be sure that if Captain Schettino had kept calm and carried on, fewer people would have died? Can it be wholly his fault if the crew were not properly trained and not even able to communicate with each other, let alone with all the passengers?
All this is special pleading, ex post facto rationalisation. Before the event, the captain accepted his own authority without difficulty or reservation. He was, however, tried and found wanting, perhaps for reasons partly cultural: not because he was Italian but because he was modern - that is to say, without an unthinking allegiance to a standard of conduct that in some circumstances might be, or might appear, ridiculous or counterproductive but in others is essential to the performance of difficult duty.
Hard cases make bad law and even worse sociology, though they are the stock in trade of philosophy, and there is no wickedness or weakness under the sun that is without precedent. Captain Schettino's story appears human, all too human: possibly a vainglorious man (but there are worse crimes than vainglory) who panicked at the one crucial moment of his career, and who will now spend the rest of his life in a state of bitter remorse and regret.
I hope it is not taken for lack of sympathy for the victims and their relations to say that, on the scale of human monstrosity, the captain does not climb very high. His place on the scale of human weakness is another matter.
As it happens, one of the great books of our literature, Lord Jim by Joseph Conrad, deals with a similar case. The hero, if that is quite the word for him, is mate on an old rust-bucket that is taking 800 Muslim pilgrims to Arabia. The boat sinks and Jim saves his skin, an act of cowardice for which he pays for the rest of his life. Marlow, the narrator of the story, describes his fate in words that resonate today:
''Nothing more awful than to watch a man who has been found out, not in a crime but in a more than criminal weakness. … from weakness that may lie hidden, watched or unwatched, prayed against or manfully scorned, repressed or maybe ignored more than half a lifetime, not one of us is safe.''
This is an edited version of an article first published in the London Telegraph.