According to the now almost universally accepted theory, all the races of mankind had a common origin.

History in its broadest aspect is a record of man's migrations from one environment to another.

The human organism inherits so delicate an adjustment to climate that, in spite of man's boasted ability to live anywhere, the strain of the frozen North eliminates the more nervous and active types of mind.

Year by year we are learning that in this restless, strenuous American life of ours vacations are essential.

In America the most widespread type of forest is the evergreen coniferous woodland of the north.

Man could not stay there forever. He was bound to spread to new regions, partly because of his innate migratory tendency and partly because of Nature's stern urgency.

The Indians could not undertake any widespread cultivation of the plains not only because they lacked iron tools but also because they had no draft animals.

Thus the races, though alike in their physical response to climate, may possibly be different in their mental response because they have approached America by different paths.

As a matter of fact, an ordinary desert supports a much greater variety of plants than does either a forest or a prairie.

Surprising as it may seem, this study indicates that similar conditions are best for all sorts of races.

The buffalo is a surprisingly stupid animal.

Although mountains may guide migrations, the plains are the regions where people dwell in greatest numbers.

For the source of any characteristic so widespread and uniform as this adaptation to environment we must go back to the very beginning of the human race.

From first to last the civilization of America has been bound up with its physical environment.

America is the last great goal of these migrations.

We are learning, too, that the love of beauty is one of Nature's greatest healers.

America forms the longest and straightest bone in the earth's skeleton.

According to the now almost universally accepted theory, all the races of mankind had a common origin.

It seems strange that almost no other traces of the strong vikings are found in America.

Curiously enough man's body and his mind appear to differ in their climatic adaptations.

The Negro, however, has been tested on an extensive scale.

The coast of British Columbia was one of the three chief centers of aboriginal America.

In fact, the history of North America has been perhaps more profoundly influenced by man's inheritance from his past homes than by the physical features of his present home.

A journey of four hundred and thirty miles can be made in any part of the United States, but in Turkey it takes as many days.

The evidence points to central Asia as man's original home, for the general movement of human migrations has been outward from that region and not inward.

Although farming of any sort was almost as impossible in the plains as in the dry regions of winter rains farther west, the abundance of buffaloes made life much easier in many respects.

Geologists are rapidly becoming convinced that the mammals spread from their central Asian point of origin largely because of great variations in climate.

Fertile soil, level plains, easy passage across the mountains, coal, iron, and other metals imbedded in the rocks, and a stimulating climate, all shower their blessings upon man.

Again and again, to be sure, on the way to America, and under many other circumstances, man has passed through the most adverse climates and has survived, but he has flourished and waxed strong only in certain zones.

The geysers and hot springs of the Yellowstone are another proof of recent volcanic activity.

No part of the world can be truly understood without a knowledge of its garment of vegetation, for this determines not only the nature of the animal inhabitants but also the occupations of the majority of human beings.

Today, no less than in the past, the tetrahedral form of the earth and the relation of the tetrahedron to the poles and to the equator preserve the conditions that favor rapid evolution.

After washing there was no place to pour the water except out of the window onto the heads of the people in the streets, which is the proper place to throw everything that is not wanted.

Except on their southern borders the great northern forests are not good as a permanent home for man.

Nevertheless most of the evergreen forests of the north must always remain the home of wild animals and trappers, a backward region in which it is easy for a great fur company to maintain a practical monopoly.

Boredom is... a vital problem for the moralist, since half the sins of mankind are caused by the fear of it.

Boldness and decision command, often even in evil, the respect and concurrence of mankind.

The proper study of mankind is books.

The creation of Physics is the shared heritage of all mankind. East and West, North and South have equally participated in it.

Our true nationality is mankind.

Mankind is not likely to salvage civilization unless he can evolve a system of good and evil which is independent of heaven and hell.

We leave as we came and, god willing, as we shall return, with peace, and hope for all mankind.

We need to teach the next generation of children from day one that they are responsible for their lives. Mankind's greatest gift, also its greatest curse, is that we have free choice. We can make our choices built from love or from fear.

I think you can leave the arts, superior or inferior, to the conscience of mankind.

As long as justice and injustice have not terminated their ever renewing fight for ascendancy in the affairs of mankind, human beings must be willing, when need is, to do battle for the one against the other.

Creation destroys as it goes, throws down one tree for the rise of another. But ideal mankind would abolish death, multiply itself million upon million, rear up city upon city, save every parasite alive, until the accumulation of mere existence is swollen to a horror.

Through all of history mankind has ingested psychedelic substances. Those substances exist to put you in touch with spirits beyond yourself, with the creator, with the creative impulse of the planet.

I refuse to accept the view that mankind is so tragically bound to the starless midnight of racism and war that the bright daybreak of peace and brotherhood can never become a reality... I believe that unarmed truth and unconditional love will have the final word.

I address myself to the Communists, to those Communists who were prompted to join the Party by the progressive ideas of mankind and socialism, and not by selfish personal interests - let us represent our pure and just ideas by pure and just means.