As they are viewed from the standpoint of human history as a whole, they show each in its own fashion a certain capacity to meet the needs and purposes of the life-force halfway.

Regarded abstractly, however, they may conveniently be treated as purely passive and limiting conditions.

Here we are with a constitution not of our choosing, and in a world not of our choosing.

Given this inheritance, and this environment, how are we, by taking thought and taking risks, to achieve the best-under-the-circumstances?
Such is the vital problem as it presents itself to any particular generation of men.
The environment is as it were the enemy.

We are out to conquer and enslave it.