Of all the arguments against voluntary euthanasia, the most influential is the slippery slope: once we allow doctors to kill patients, we will not be able to limit the killing to those who want to die.

Evolution has no moral direction. An evolutionary understanding of human nature can explain the differing intuitions we have when we are faced with an individual rather than with a mass of people, or with people close to us rather than with those far away, but it does not justify those feelings.

Unfortunately for ethical egoism, the claim that we will all be better off if every one of us does what is in his or her own interest is incorrect. This is shown by what are known as "prisoner's dilemma" situations, which are playing an increasingly important role in discussions of ethical theory... At least on the collective level, therefore, egoism is self-defeating - a conclusion well brought out by Parfit in his aforementioned Reasons and Persons.

What is faith? If you believe something because you have evidence for it, or rational argument, that is not faith. So faith seems to be believing something despite the absence of evidence or rational argument for it.

If governments did not mislead their citizens so often, there would be less need for secrecy, and if leaders knew they could not rely on keeping the public in the dark about what they are doing, they would have a powerful incentive to behave better.

Of all the arguments against voluntary euthanasia, the most influential is the slippery slope: once we allow doctors to kill patients, we will not be able to limit the killing to those who want to die.

We should give the same respect to the lives of animals as we do to the lives of humans.