Man should study the Kama Sutra and the arts and sciences subordinate thereto, in addition to the study of the arts and sciences contained in Dharma and Artha. Even young maids should study this Kama Sutra along with its arts and sciences before marriage, and after it they should continue to do so with the consent of their husbands. Here some learned men object, and say that females, not being allowed to study any science, should not study the Kama Sutra. But Vatsyayana is of opinion that this objection does not hold good, for women already know the practice of Kama Sutra, and that practice is derived from the Kama Shastra, or the science of Kama itself. Moreover, it is not only in this but in many other cases that though the practice of a science is known to all, only a few persons are acquainted with the rules and laws on which the science is based. Thus the Yadnikas or sacrificers, though ignorant of grammar, make use of appropriate words when addressing the different Deities, and do not know how these words are framed. Again, persons do the duties required of them on auspicious days, which are fixed by astrology, though they are not acquainted with the science of astrology. In a like manner riders of horses and elephants train these animals without knowing the science of training animals, but from practice only. And similarly the people of the most distant provinces obey the laws of the kingdom from practice, and because there is a king over them, and without further reason.[11] And from experience we find that some women, such as daughters of princes and their ministers, and public women, are actually versed in the Kama Shastra.