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.
In the specific case of abortion, the matter is particularly easy in that no woman wants a late abortion. Once abortion was made legal, the age of the aborted fetus went down. The slope slipped in the other direction. If we legalize RU-486 and other similar new drugs, the age will fall to one week or less and start approaching zero. The slippery slope will slide in the other direction. The only reason we have late abortions is because we make early abortion difficult.
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.