This is the first of a series of lectures on suicide. Two very distinct contexts are presented in which the subject can be further explored. The first is rationality and the question of under what circumstances it makes sense to end one's own life. The second is morality and the question of whether we can ever ethically justify resorting to suicide. The lecture's focus is on the rational requirements of suicide, and Professor Kagan introduces a number of cases which demonstrate that ending one's life, in certain instances, may be rationally sound.