Death may not be a particularly cheery subject to reflect on, but on occasion it pulls us up short and requires us to examine ourselves, our societies, and asks us to learn.
Two recent losses in their different ways serve as both warnings and guides.
The tragic case of Trayvon Martin, shot dead half a world away in Sanford, Florida, and which now has race relations in the United States at their most taut in years, exposes everything that is wrong with self-help movements of policing and justice: all too often they tip over into the prejudice-fuelled territory of vigilantism whereby largely self-appointed guardians of the public good, acting according to their own impulses, their personal suspicions and dislikes, take the law into their own hands.
This is not helped when the law of the land - the state, or country - explicitly seems to encourage such behaviour.
For those who have not yet caught up with this appalling incident, George Zimmerman, leader of a local community neighbourhood watch organisation, shot dead Trayvon (17) as he walked home with a bag of sweets for his little brother. His apparent crime?
He was black and wearing a hoodie.
Zimmerman claimed to local police he shot the boy in self-defence but the police despatcher's records tend to indicate a different scenario, one in which the neighbourhood watch man signalled his suspicions about the boy ("He looks like he's black; [he's wearing] a dark hoodie"); and in which he confirmed these views with the comment, "This guy looks like he's up to no good".
Local police say they believed the shooter's claim he was attacked from behind by the boy. Doubtless they were aided in their decision neither to arrest Zimmerman, nor to charge him, by Florida's 2005 "Stand Your Ground" law which allows citizens to use deadly force if they believe they are threatened.
Racial profiling, easy accessibility of weaponry and gung-ho so-called self-protection laws make it just too easy for those tripping on self-righteous intent, fuelled by aggressive pre-conceived notions, to commit murder and get away with it.
The resignation of the Sanford police chief and the rallies now taking place across the United States in protest at this killing suggest Zimmerman, if he is indeed guilty, will not get away with it; at least not without a trial.
Hopefully, it might also lead authorities in Florida to look again at the apparent licence to kill that its Stand Your Ground law might seem to deliver.
If the death of Trayvon Martin serves as a depressing warning of how prejudice and poor law can conspire to commit dreadful acts, a departure much closer to home is cause to reflect on the wisdom and generosity of the human spirit.
I am talking about the death at the weekend of Sir Paul Callaghan, one of this country's most brilliant scientists, and a peerless communicator of his vast depositories of arcane knowledge.
Like many New Zealanders, I became familiar with Sir Paul through his scientific chats with National Radio broadcaster Kim Hill - to whom no small credit is due for her elucidatory, inquisitorial role.
No subject seemed too complex for him to address, whether black holes or electromagnetic resonance. His rare and precious skill was to be able to simplify, to render into everyday parlance and understanding that which, by rights, and in the hands of lesser talents, keenly resisted explication.
That he did so with a quiet humility coupled with an almost tangible passion for his subject made even the driest of subject matter compelling. He also made it possible for even those of us slow to grasp the essence of his chats to feel included and clever. That is a rare skill indeed.
But last year's New Zealander of the Year - the most recent in a long line of national and international honours he received throughout his prestigious career - did not confine himself to the endeavours of science alone; or not, at least, of science in a vacuum.
He wrote and spoke equally eloquently about economics, about human capital, about society, about social inequality and income disparity and how New Zealand might be transformed into a niche world-leading high-tech society.
Inherent in it all was a deep sense of commitment to a just, inquiring, innovative and inclusive New Zealand.
He believed it was possible and he made most who had the privilege of listening to him believe it, too.
Sir Paul's death, deeply saddening, nonetheless demands we acquaint ourselves with his legacy in all its generosity and wisdom, and be uplifted.
- Simon Cunliffe is deputy editor (news) at the Otago Daily Times.