When one sees the opposite sex, naturally the sex impulse increases. It is said that if a man in a solitary place does not become agitated upon seeing a woman, he is to be considered a brahmacari. But this practice is almost impossible
SB Canto 4
On the outskirts of that city were many beautiful trees and creepers encircling a nice lake. Also surrounding that lake were many groups of birds and bees that were always chanting and humming.
Since the body is a great city, there must be various arrangements such as lakes and gardens for sense enjoyment. Of the various parts of the body, those which incite sexual impulses are referred to here indirectly. Because the body has genitals, when the living entity attains the right age—be he man or woman—he becomes agitated by the sex impulse. As long as one remains a child, he is not agitated by seeing a beautiful woman. Although the sense organs are present, unless the age is ripe there is no sex impulse. The favorable conditions surrounding the sex impulse are compared here to a garden or a nice solitary park. When one sees the opposite sex, naturally the sex impulse increases. It is said that if a man in a solitary place does not become agitated upon seeing a woman, he is to be considered a brahmacārī. But this practice is almost impossible. The sex impulse is so strong that even by seeing, touching or talking, coming into contact with, or even thinking of the opposite sex—even in so many subtle ways—one becomes sexually impelled. Consequently, a brahmacārī or sannyāsī is prohibited to associate with women, especially in a secret place. The śāstras enjoin that one should not even talk to a woman in a secret place, even if she happens to be one's own daughter, sister or mother. The sex impulse is so strong that even if one is very learned, he becomes agitated in such circumstances. If this is the case, how can a young man in a nice park remain calm and quiet after seeing a beautiful young woman?