It's been long a tradition in Western medicine that to qualify as a doctor, medical students have to first learn gross human anatomy by dissecting human bodies.

In 19th century England and America, medical students had to pay for the procurement of these bodies, which led to a lucrative trade plied by a network of body-dealers who made money by scrounging for and selling fresh corpses that, in most cases, were either unclaimed bodies or those whose relatives were too poor to pay for a proper burial.

And there were also the "resurrectionists" - grave robbers, who with their shovels, pickaxes and ropes, were particularly adept at stealing bodies from fresh graves. Worried families would hire night-time guards at the grave site - hence the term "graveyard shift"; others would place heavy rocks on the coffins. There was even an American company that specialised in making "torpedo coffins" that were booby-trapped with bombs that would explode when tampered with. The wit and writer, Ambrose Bierce, in his book The Devil's Dictionary (published in 1906) defined a "grave" as "a place in which the dead are laid to await the coming of the medical student".

ANATOMY CLASSES

While those macabre days are long over, the study of human anatomy in many medical schools today is still via that time-honoured dissection of cadavers. That was how I'd learnt the human anatomy when I was a medical student in the early 1980s.

I remember, on the first day of medical school, turning up with my classmates at the dissection hall for our anatomy lesson, which for most of us was also our first encounter with a cadaver. In the cavernous hall, scores of cadavers were laid out on stainless steel tables: naked, stiff, shrivelled, dusky corpses reeking of formaldehyde that made our eyes water. We were divided into groups of five or six and each group was assigned a cadaver.

Over the next two years, we would spend a certain number of hours every week cutting through the waxy leathery skin with the underlying yellow subcutaneous fat; minutely dissecting muscles, tendons, vessels and nerves, identifying them and tracing their origins and destinations and removing one internal organ after another for further examination.

We were never told of the origins of these cadavers. I didn't know who my cadaver was; neither did I know his age, race, or the cause of his death. His gaunt and seemingly ascetic face reminded me of those mediaeval effigies of holy men and knights carved on the lids of sarcophagi. Because he was an enigma, my mind occasionally strayed and I wondered about the sort of person he had been, the life he had, and how he had died - possibly alone, nameless and unclaimed. I can't say it was sadness that I felt, but rather an occasional and unbidden disquiet and an inchoate guilt that I couldn't quite understand then.

In his autobiography When Breath Becomes Air, neurosurgeon Paul Kalanithi, in recalling his early medical school days, described cadaver dissection as "a medical rite of passage and a trespass on the sacrosanct" that had invoked "a legion of feelings: from revulsion, exhilaration, nausea, frustration, and awe to, as time passes, the mere tedium of academic exercise".

The anatomy professors had advised his class to take a good look at their cadavers' faces and then leave them covered. Objectivising the cadaver and not seeing it as a person, so it seemed, made their task easier and kept their minds focused for the dispassionate study of the topography of the human body.

It would have been something that Diogenes, a Greek philosopher who lived two-and-a-half millennia ago, would have endorsed: He had wanted his students to throw his corpse over the city wall where it would be devoured by animals. His corpse, which he viewed as "smelly, putrefying flesh that had lost whatever had made it alive", would not matter to him. "What harm then can the mangling of wild beasts do me if I am without consciousness?" he asked.

But most people would recoil from Diogenes' unsentimentally rational but chilly view about the materiality of the corpse. We see the dead body of someone we know as some version of that living person and where a large remnant of that personhood remains tethered to that corpse. And even if we didn't know the person, we would imagine a life for that body and not see it as a mere empty husk. We can't help but have strong atavistic feelings towards the dead and we care very much about what happens to these mortal remains, including our own. Most societies value the sanctity of life as well as the sanctity of the corpse.

And so, seen in that context, dissection is a transgression of social norms. While it is sanctioned in the name of medical education, it still - in the words of the author of a book on dissection (Death, Dissection, And The Destitute) - "requires in its practitioners the effective suppression of many normal physical and emotional responses to the wilful mutilation of the body of another human being".

Medical sociologist Renee Fox, who in the 1950s had spent some time among medical students dissecting human bodies, found that most of these students were distressed by this experience but managed to keep a tight lid on these emotions, and learnt to - albeit implicitly - cultivate a "detached concern" that was deemed essential for their future medical practice.

This received wisdom persisted; and two decades later, another sociologist, Frederick Hafferty, made the disconcerting observation that there was more detachment than concern among the cohort of medical students he had studied.

He surmised that the dissection hall was a sort of boot camp where neophytes to the medical community first learn to manage disturbing experiences without revealing weakness or emotion; dissecting was therefore an "emotional Rubicon" separating the strong from the weak.

It's hardly surprising then that Kalanithi had asserted that "cadaver dissection epitomises, for many, the transformation of the sombre, respectful student into the callous arrogant doctor" - but that kind of attitude is not what we want our doctors to have.

Experts on medical education have alleged that the suppression of these natural emotions and impulses would have undesirable consequences - including the lack of empathy. Studies have linked empathy to greater patient satisfaction, better outcomes, decreased physician burnout, and a lower risk of malpractice suits and errors. It enables a doctor to see beyond the physical aliment and see the person with all his feelings and emotions, his fears and hopes.

CARE FOR THE DEAD

Things are now different in most medical schools where anatomy is still being taught through dissection. Reforms have been carried out. There is now a greater sensitivity to the emotional reactions of the students, and proper deference has been accorded to the dead bodies, which are no longer viewed as mere pedagogical material. And these changes have made the idea of donating one's body for the training of a future generation of doctors more palatable.

A recent article in The Straits Times reported that the Department of Anatomy of the NUS Yong Loo Lin School of Medicine has been able to resume dissection of cadavers after a cessation of many years. This was due to an increase in body donation achieved largely through a donor programme.

Medical students have to take the Anatomy Student's Oath to emphasise the importance of approaching these bodies (which are called "silent mentors") with respect. They are told of the donor's history and see a photograph of the person when he or she was alive, and every year the faculty and students would organise and participate in an appreciation and memorial ceremony as a show of respect and gratitude to the donors and their families.

Other medical schools have drawn on the humanities to encourage their students to use writing and art to express their feelings, and discuss issues of dying and death, which would be commonplace once these students start practising as doctors.

Some might see this as too touchy-feely, too maudlin. But the dead matters to us because death and its attendant mystery are entrenched in our human intuition and feeling; to honour and respect the dead is something that makes us human - never mind if it is also irrational. In embracing that quintessentially human desire to care for the dead, we would somehow learn to care more for the living and for life.

As for those generous individuals who donate their bodies, they should know that it is not just the nascent clinical and technical acumen that are being developed in these students. What is just as important is that they are helping to train doctors who are empathic and not afraid of emotions, and who realise how their emotions may be brought to bear in their efforts to help their patients.

Perhaps then, it is fitting for the training of a doctor to start not with an introduction to the living but to the dead.

•The writer, a psychiatrist, is vice-chairman of the medical board (research) at the Institute of Mental Health.