A coldly rationalist individualist can deny that he has any obligation to make sacrifices for the future.

The morality of an act is a function of the state of the system at the time it is performed.

The only kind of coercion I recommend is mutual coercion, mutually agreed upon by the majority of the people affected.

The exquisite sight, sound, and smell of wilderness is many times more powerful if it is earned through physical achievement, if it comes at the end of a long and fatiguing trip for which vigorous good health is necessary. Practically speaking, this means that no one should be able to enter a wilderness by mechanical means.

You cannot do only one thing.

Value is a relative concept: the value of each action is determined by comparing it with other possible actions.

A technical solution may be defined as one that requires a change only in the techniques of the natural sciences, demanding little or nothing in the way of change in human values or ideas of morality.