Jeevaka on contemplation of his studies was asked by his guru to go to the forest and bring any herb that was not medicinal. Jeevaka went to the forest. He examined each and every herb in the forest and found that all the plants available have some medicinal application. He returned to his guru and admitted that he was unable to find any plant that was not medicinal.
The guru was delighted and blessed Jeevaka and permitted him to practice medicine. In Ayurveda the permission of the guru is very important in starting practice.
[blockquote-right cite=””]In this universe, nothing is available which cannot be utilized for medicinal purpose.[/blockquote-right]