Few things seem more certain than death.

However, precisely when death occurs is less certain than it used to be. People who would have been given up for dead 100 years ago get a second chance today. More disturbingly, bodies that still show vital signs may actually be dead. Such developments are generating impassioned debates about how we deal with death, the dead and the dying.

We can look to the usual suspects for an explanation: The heat generated by huge advances in technology rubbing against traditional beliefs and customs is only intensified by the fact that they are struggling over something as primordial as death.

Knowing who was dead used to be a relatively simple business. Cultures may have differed as to which sign they took as decisive, but the absence of breath or of heartbeat would lead to the same conclusion anywhere. Once that happened, there was little that could be done. All that remained was for those left behind to deal with their loss, usually through religious beliefs and funerary customs.

Things are no longer that simple. Even without breath and a heartbeat, all may not be lost. If paramedics (not even doctors!) get to you in time, your heart may be restarted and your breathing restored. On the other hand, you may lie on a hospital bed with your body warm and your heart beating, but with no known chance you will ever revive.

To get around these now-possible impossibilities, the concept of "brain death" was developed in medicine and has since passed into wider usage in Japan and elsewhere.

At the same time as the technology for saving people has exceeded the dreams of 100 years ago, the technology for transferring organs from one person to another has moved from science fiction to science fact.

Such technology is throwing traditional views about the integrity of the individual's body and soul against compassion and the desire to help others. In Japan, people who oppose the concept of brain death claim that Japanese beliefs about the body, the soul and death prevent these "alien" ideas and practices from finding acceptance here.

An ancient animism, underlying Shinto, regarded all people, animals, trees, and even rocks, as having souls. It is said that a belief that those souls exist throughout the body prevent Japanese people from accepting that the death of only one part, the brain, is the death of the whole.

Also, we are told, the Japanese believe that a dead person goes into the next world with senses similar to those of a living person. And because the soul exists throughout the body, the latter must be complete for the funerary rites. If not, the deceased may become unhappy and visit all sorts of afflictions upon surviving family members. Consequently, both brain death itself and transplants are supposed to be unacceptable to Japanese people. But are they?

Surveys conducted since 1985 show that a majority of Japanese people accept brain death to constitute actual death. On the official level, both the Japan Medical Association and a special prime ministerial committee on brain death and transplantation reached the same conclusion. In addition, only a small minority is opposed to organ transplants. This puts paid to the idea of cultural incompatibility.

But why, then, do organ transplants remain rare in Japan? It seems that many ordinary Japanese distrust their doctors. They feel that doctors refuse to tell them important information. They also feel that the closed nature of Japanese medicine's ethics means that patients have no effective redress against doctors' negligence.

In such a medical culture, it is understandable that ordinary Japanese fear being left uninformed, at best, or even deliberately misled during the determination of brain death or decisions about transplantation. Hence, they resist both.

In similar circumstances, the citizens of many other countries would surely do the same.