Terry Pratchett: Why stop trusting a doctor who has the power to kill you?

If we are are to live in a world where a socially acceptable "early death" can be allowed, it must be allowed as a result of careful consideration. Let us consider me as a test case. As I have said, I would like to die peacefully with Thomas Tallis on my iPod before Alzheimer's disease takes me over and I hope that will not be for quite some time to come, because if I knew that I could die at any time I wanted, then suddenly every day would be as precious as a million pounds. If I knew that I could die, I would live. My life, my death, my choice.

There has been no evidence in those areas where assisted dying is currently practised that it leads to any kind of "slippery slope". It seems to be an item of faith among those opposed to assisted dying that it will open the door to abuses all the way up to the culling of the elderly sick. This is a nightmare and only a nightmare. This cannot be envisaged in any democracy unless we find ourselves under a tyranny. Frankly, that objection is a bogeyman.

It has been suggested that people would not trust their doctor if they knew that they had the power to kill them. Why should this be? A doctor has an awful lot to lose by killing a patient. Indeed, it seems to me that asking a medical practitioner, who is fully aware of your situation, to bring your life to an end is placing the utmost trust in them.

The saying "Though shall not kill; but needst not strive officiously to keep alive" has never been formal advice to the medical profession. Given that it was made up by Arthur Hugh Clough, who was in a similar profession to me, that is not surprising. But, ever since the birth of medicine, doctors have understood its meaning. They have striven, oh how they have striven. In the past two centuries we have improved the length of our lives and the quality of said lives to the point where we feel somewhat uneasy if anyone dies as early as the biblical age of 70. But there comes a time when technology outpaces sense, when we believe a blip on an oscilloscope is confused with life, and humanity unravels into a state of mere existence.

Observation, conversation and some careful deduction lead me to believe that the majority of doctors who support the right to die are those who are most closely involved day-to-day with patients, while support appears tail off as you reach those heights where politics and medicine merge.

Taken from the author's Dimbleby Lecture last night