The Siddha system is comprised essentially of philosophical concepts and also the following four components:
According to Siddha medicine, every substance is understood by five characters, which depend upon the elements present in them. They are taste, property, potency, post digestive transformation and unique biological activity or specific pharmacological action.
Human is the microcosm and the Universe, the macrocosm; what exists in the Universe also exists in human. Therefore, human must be looked upon as an integral part of the Universe. Further, the matters in the microcosm or human are identical with those of the macrocosm or the Universe.
Diagnosis is based on the following eight kinds of diagnostic tools — Pulse (N¡¶i), Perception by palpation (Paricam), Tongue (N¡), Complexion (Ni¼am), Speech (Mo¾i), Eye (Vi¾i), Faeces (Malam) and Urine (M£ttiram). Examination of pulse and urine are very important because they are helpful not only in arriving at the diagnosis but also in assessing the prognosis of the disease. In Siddha system, apart from the eight investigatory tools of diagnosis described above, the measurement of wrist circumference by an inelastic thread expressed in terms of four finger-breadth (excluding thumb) of the patient forms another diagnostic tool called Ma¸ikka¶ai n£l