Man's mind is his basic tool of survival. Life is given to him, survival is not. His body is given to him, its sustenance is not. His mind is given to him, its content is not. To remain alive, he must act, and before he can act he must know the nature and purpose of his action. He cannot obtain his food without a knowledge of food and of the way to obtain it. He cannot dig a ditch -- or build a cyclotron -- without a knowledge of his aim and of the means to achieve it. To remain alive, he must think.
But to think is an act of choice. The key to what you so recklessly call "human nature", the open secret you live with, yet dread to name, is the fact that man is a being of volitional consciousness. Reason does not work automatically; thinking is not a mechanical process; the connections of logic are not made by instinct. The function of your stomach, lungs or heart is automatic; the function of your mind is not. In any hour and issue of your life, you are free to think or to evade that effort. But you are not free to escape from your nature, from the fact that reason is your means of survival-so that for you, who are a human being, the question "to be or not to be" is the question "to think or not to think."
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In the name of the best within you, do not sacrifice this world to those who are its worst. In the name of the values that keep you alive, do not let your vision of man be distorted by the ugly, the cowardly, the mindless in those who have never achieved his title.
Do not lose your knowledge that man's proper estate is an upright posture, an intransigent mind and a step that travels unlimited roads. Do not let your fire go out, spark by irreplaceable spark, in the hopeless swamps of the approximate, the not-quite, the not-yet, the not-at-all.
Do not let the hero in your soul perish, in lonely frustration for the life you deserved, but have never been able to reach. Check your road and the nature of your battle. The world you desired can be won, it exists, it is real, it is possible, it's yours.
But to win it requires your total dedication and a total break with the world of your past, with the doctrine that man is a sacrificial animal who exists for the pleasure of others. Fight for the value of your person. Fight for the virtue of your pride. Fight for the essence of that which is man: for his sovereign rational mind. Fight with the radiant certainty and the absolute rectitude of knowing that yours is the Morality of Life and that yours is the battle for any achievement, any value, any grandeur, any goodness, any joy that has ever existed on this earth.
You will win when you are ready to pronounce the oath I have taken at the start of my battle -- and for those who wish to know the day of my return, I shall now repeat it to the hearing of the world:
"I swear -- by my life and my love of it -- that I will never live for the sake of another man, nor ask another man to live for mine." -John Galt, Atlas Shrugged