A fact which you cannot afford to ignore is that every thought you send out or attract to you lends its influence either toward the prolongation or limitation of your life. Cheerfulness is a potent factor in the attainment of a long healthy life. Genuine merriment is also a real factor in the promotion of physical health. The man or woman who desires to live long must not forget to laugh, and it must be joyous, unrepressed laughter. Every centenarian I have conversed with was in the habit of looking on the bright side of things. They all possessed remarkably cheerful temperaments. Cultivate the habit of thinking how to better your life and how to help your fellow-men. It is the man who uses his power of thought that lives, not only many years, but lives in the brains of other men for ages after his physical body has returned to dust.

Another rule for you to follow is to constantly hold the ideal of youth before your mental vision. Do not say, "Oh, dear me! I am growing old and feeble; the years are swiftly passing and it will soon be time for me to go." Hold firmly to the thought that you are young and that you will express youth in spite of passing years.

It is well known to physiologists that the cells and atoms of the body are in a constant state of change, that new atoms can be and are attracted to take the place of the old ones. Under normal conditions the softer parts of the body are changed about every thirty days, the brain cells in about sixty days, and the hardest bones in about a year. Thus you see we can all affirm with perfect truth that we do actually possess youth at all times. Science demonstrates that physical age is a fallacy and an utter impossibility.

At all periods of your existence be conscious of the fact that your body is new, and never suggest to yourself nor accept the suggestion from others that you are growing old. If you continue to entertain the thought that you are growing old, it will affect the body adversely, repress the normal process of renewal, and the body will gradually assume the characteristics of age.

Students of psychology will at once see the unlimited power contained in this secret of physical renewal in its relation to health and long life. How easy and natural it becomes to suggest youthful energy and vim when we know that we are actually physically young.

Remember that your legal age, whatever it may be, does not represent your bodily age. Your legal age may be fifty, but it would not be true to say that your body is fifty years old, for it has been entirely built up atom by atom from food and air during the past year. That you may obey the laws of mental hygiene, you must form the habit of regarding your body as new in all its parts, both internal and external.

If you care to make the experiment, you can easily prove the efficacy of this rule. For one day hold the thought that you possess an aged body. As you work or move, think of your arms, hands and fingers as old and gradually growing older. As you walk think of your legs as old and feeble and showing the gradual approach of decrepitude. If you survive the day, you will never venture to try the experiment again. The sensations you will experience and suffer will be anything but pleasant. Understand, I do not advise you to try this experiment. I would suggest, however, that you try the opposite experiment. For one day make it a special point to carry the thought that the constant changing of the bodily atoms is making your body new and plastic. Make this distinct affirmation, "My body is new and full of youth. This newness enables me to pursue my daily activities with ease and pleasure." It is no exaggeration to say that, as this true suggestion grows in intensity and realization from the repeated affirmations, you will feel your entire body tingle with a new influx of vital power.

These simple experiments will demonstrate to you the necessity of strictly maintaining the right mental attitude. The latter experiment you must make a part of your daily life. I do not mean that you must become unduly conscious of your body, but simply that you must consciously guide your thought in the right channels until it becomes a normal habit, requiring no special attention.

Look at yourself as you are today. Do you see any imperfections? If so, set up in your mind a mental picture of just what you want to be. If you will bear in mind that in one year your entire body passes through a complete change, and also turn your attention to living the life, as explained in these lessons, which will make it most easy for you to accomplish your desires, I can assure you that at the end of a year you will be much nearer what today you wish to be. Each year you can add new perfections and each year build up a higher ideal for the future. In this way you can progress perpetually.

When we seek to cultivate long life upon a mental basis, we are laying the foundation for a true hygienic life. It matters not how pure and nutritious our food may be, assimilation will be imperfect if the mind is not in harmony. Unpleasant thoughts and adverse suggestions will spoil the best meal that can be prepared. A definite factor in the attainment of enduring health and youth is the preservation of a harmonious state of mind. You positively injure yourself and others when you lose your self-control and give way to anger or irritability.

It is beautiful to realize the truth that harmony of thought, speech and action create health and harmony for all the physical functions. Harmony combined with determination will accomplish wonders. To outsiders the result appear as marvelous, while in reality it is but the simple workings of Nature through a normal brain.

To assure yourself of a century of vigorous life, you must arouse your will to supreme activity. You must truly believe that the power to live a hundred years is within you. Grasp the vital principles explained in these lessons and see that your will power is steadily directed towards life's attainment.

By the exercise of harmonious will power and thought force, invalids have left beds of sickness and regained perfect health after their cases had been pronounced hopeless by expert physicians They willed to live and demonstrated the power of mind to control the body. A weak, uncertain will is equivalent to a short life of imperfect health. The exercise of the will to live and retain or regain youth revitalizes and renews the life elements. The power of the will must, of course, be used in conjunction with hygienic modes of living. The exercise of the will without proper food, air, rest, etc., to supply the material for new cells and tissue, would, of course, produce less satisfactory results.

As life is a constant process of change, birth and death are always occurring in your body. Therefore, you must not direct your will power toward the conquest of death, but toward the establishment of harmony and balance between wear and repair. In this way you will be following the scientific attitude which assures you of the attainment of long life. It cannot be repeated too often that harmony always gives to thought an intensified power. Your capacity to renew life through thought is greatly increased when you try to harmoniously co-operate with the life forces and recognize that Nature is always your friend and servant.