Ayurveda is a considered as a “PANCHAM VEDA” It is a UPVEDA of “ATHARVAVEDA”. The word It means the subject which can gives the knowledge about how can a person lives a longer & healthy life.
There are mainly 8 branches of

(INNER MEDICINE) (PAEDIATRICS)   (DEMONOLOGY) (Treatment of diseases of head & Sensory organs)   (SURGERY)   (TOXICOLOGY) (GERIATRICS)  (VIRLIFICATION THERAPY)

Dharma, Artha & Sukha (Kama & Moksha) are known as Purusarthas means these all three are the main aims of human life. To attain these a long & heallty life is essential. Ayurveda teaches to how to have such a life. Hence the insistence on keeping full faith in the teaching of this science.
Therefore in Ayurveda there is a one slogan given,