When this seminal collection of essays was first published in 1978, the philosophical 'problem' of obligations to fixture generations was not widely recognised. But as the contributors point out, the theories that have constituted the stock-in-trade of moral philosophers for the past two hundred years often produce weird and counter-intuitive results when they are extended to try to include those who are as yet unborn. Utilitarianism can appear to recommend practically unlimited population increase, with quantity of life taking precedence over quality; theories based on a social contract...