Numeracy: 1. The art of putting numbers to things, that is, assigning amounts to variables in order that practical decisions may be reach. 2. That aspect of education (beyond mere literacy) which takes account of quantitative aspects of reality.

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

No one should be able to enter a wilderness by mechanical means.

A finite world can support only a finite population; therefore, population growth must eventually equal zero.

It takes five years for a willing person's mind to change. Have patience with yourself and others when treading in an area protected by a taboo.

In a finite world this means that the per capita share of the world's goods must steadily decrease.

Indeed, our particular concept of private property, which deters us from exhausting the positive resources of the earth, favors pollution.