The Kama Sutra was composed, according to the precepts of Holy Writ, for the benefit of the world, by… — Vatsyayana

A man may resort to the wife of another, for the purpose of saving his own life, when he perceives that his love for her proceeds from one degree of intensity to another. These degrees are ten in number, and are distinguished by the following marks:

1. Love of the eye

2. Attachment of the eye

3. Constant reflection

4. Destruction of sleep

5. Emaciation of the body

6. Turning away from objects of enjoyment

7. Removal of shame

8. Madness

9. Fainting

10. Death

Man, the period of whose life is one hundred years, should practise Dharma, Artha, and Kama at different times and in such a manner that they may harmonize, and not clash in any way. He should acquire learning in his childhood; in his youth and middle age he should attend to Artha and Kama, and in his old age he should perform Dharma, and thus seek to gain Moksha, that is, release from further transmigration.

A man should fix his affections upon a girl who is of good family, whose parents are alive, and who is three years or more younger than himself. She should be born of a highly respectable family, possessed of wealth, well connected, and with many relations and friends. She should also be beautiful, of a good disposition, with lucky marks on her body, and with good hair, nails, teeth, ears, eyes and breasts, neither more nor less than they ought to be, and no one of them entirely wanting, and not troubled with a sickly body. The man should, of course, also possess these qualities himself.