The poetic wave from Persia came to India, and it was with this wave that the poetry of India changed its character. The Hindus, who have always been exclusive and remote, and followers of tradition, did not at first adopt the Persian form, so that in India two different aspects of poetry were developed. One aspect was the poetry written in one of the Prakrits, the vernaculars which had superseded Sanskrit both as a spoken language and in some forms of literature. It is said that the Prakrit languages were formed by Yogi powers and spiritual inspiration. The poets expressed wonderful ideas in Prakrit poetry, and they generally followed the same meters as in Sanskrit; they used many Sanskrit words, although the languages as a whole were Prakrits. Only in rhythm a new form was introduced, in which the vowels attached to different consonant letters were not heeded any more, and words and ideas were arranged so as to follow only the beat of the rhythm. In this way they were quite free to express themselves as long as they could beat the time in their minds, without being tied to the rigid system of syllables prevalent in Sanskrit poetry, as explained in the previous chapter.