Tastes, which are possessed of dry, light or expansive potencies, fail to pacify the deranged Vayu, though otherwise they may prove soothing to that deranged humour. Similarly, tastes, which are ordinarily reckoned as pacifiers of the deranged Pittam, fail to produce that effect in the event of their being endued with a keen, light or heat-making potency. Likewise, tastes, which are commonly found to soothe the deranged Kapham, tend to aggravate it in the event of their being possessed of potencies which are respectively heavy, cool and emollient in their character. * Hence the potency of a drug is the most important factor in the science of medicine.
But certain authorities dissent from the above-said view, and attach the highest importance to the process of digestive (chemical) reaction (Vipaka) for the reason, that all ingested food, properly or improperly digested in the stomach, proves wholesome or otherwise to the body. Certain authorities on the subject hold that digestion develops all the several tastes. †
According to others, tastes such as, sweet, pungent and acid follow upon the completion of the process of digestion (by way of reactionary result or transformation).
* Flavours such as, sweet, acid and saline, subdue the deranged Vayu. Tastes such as, sweet, bitter and astringent are antibilious in their efficacy, while those, which are pungent, bitter and astringent, are antiphlegmagogic in their virtues.
† The process of digestion is followed by a reactionary taste, which may be either sweet, pungent, acid, astringent, bitter or saline.
It is needless to say that the hypothesis is based on erroneous data, inasmuch as the fact of acid digestion (acid taste developed at the close of the digestive process or reactionary acidity) is contrary both to the properties of matter and the collective experience of the race embodied in the dictum of the Shastras,and which should be rather ascribed to the acid taste of the Pittam remaining in an undigested or unassimilated condition owing to imperfect gastric digestion. The probability of a saline digestion (a reactionary saline taste following upon the close of the digestive process) should be necessarily presumed, if the fact of an acid digestion were to be upheld as a tested and corroborated principle of medical science. The hypothesis of an acid digestion (reactionary acidity) does not preclude the possibility of a similar saline one owing to the participation of the natural taste (saline) of the bodily Kapham in the process of digestion, as is said of Pittam in the preceding instance. Hence the theory that only three tastes, such as sweet, acid, and pungent are developed through digestive reaction, appears to be untenable, and naturally points to the doctrine that a sweet taste (partaken of by a man) brings on a sweet tasted digestion; an acid taste (reactionary acidity) begets acid digestion, and so on, a taste of whatsoever kind partaken of by a man imparting its specific character to his digestive reaction.
Those, who adhere to the last named doctrine, endeavourto substantiate it by the following analogy, and argue that as milk kept boiling in a basin placed over a fire does not change its natural sweetness (with the change of its temperature), as cereals such as Sbali-rice, wheat, barley, Mudga, etc. sown broadcast in the ground do not part with their inherent, generic attributes (through their successive stages of development), so the tastes of food-stuff do not alter even after being boiled in the heat of the digestive organs.
Others, on the contrary, assert that weak tastes are naturally merged in the strong ones in the course of digestion. And since the consensus of expert opinions on the subject serves only to increase the confusion on account of their differences and bigoted antipathy, we shall judiciously refrain from indulging in idle theories on the subject.
Only two kinds of digestion (digestive reactionary tastes) have been noticed in the Shastras, such as, the sweet and the pungent, the first being heavy and the second light. The specific properties of the five essential material principles of the world such as, the earth, water, fire, air and sky may be roughly described as heaviness and lightness, the two attributes which appertain to their fundamental natures. Heaviness forms the characteristic attribute of earth and water, while lightness stands for the essential properties of fire, air and sky. Hence the digestion of all food-stuff may be described as either heavy (Guru) or light (Laghu).
Of substances under the process of digestion, those, which are characterised by attributes, specifically belonging to earth and water, are called substances of sweet (heavy) digestion; while those which are permeated with the specific properties of air, fire and sky are called substances of pungent (light, digestion (easily digestible articles of food). We have fully stated the text of the controversy as regards the primary importance of drugs and their tastes, virtues, potencies and digestive reactions, as well as the views of those who build their theories on the separate or exclusive importance of any of the five afore-said factors. The wise and the erudite set an equal importance to each of them, and ascribe the curative efficacy of a medicine to the co-operation of all these five factors. A drug or a substance sometimes destroys or originates a deranged condition of the humours through the dynamical action of its native or inherent properties, sometimes in virtue of its specific potency and sometimes by natural taste or digestive (chemical) reaction. Digestive reaction is impossible without drug potency. There is no potency without a taste, and taste without a drug or substance is an absurdity. Hence a substance (vegetable or otherwise) is the greatest of them all. A taste and a substance are correlative categories from the time of their origin, like a body and an embodied self in the plane of organic existence. Since an attribute perse can not be possessed of another attribute, the eight kinds of potency (properties) can only appertain to a substance and not to a taste, which is an attribute in itself. Substances are digested in an organic body and not the six tastes simply for the reason of their being invisible and intangible in themselves. Hence a substance is the greatest of all the aforesaid five factors (of substance, taste, virtues, etc.) and the attributes lie inherent in the substance.
Unscrutable and unthinkable are the virtues of drugs (medicines), which are above all rules of syllogism; and hence drugs (medicines), which have been observed to be efficacious from time immemorial, as well as those laid down in the scriptures on medicines, should alone be used in the course of a medical treatment, A learned physician should think it a sacrilege to logically dispute the efficacy of a medicine of tested virtue, and which has been adopted after generations of careful observation and is instinctively pronounced by men as a beneficial remedy.
No amount of logic will alter the nature of things, nor persuade the drugs of the Amboshtha group to exercise a purgative virtue. Hence an intelligent physician should adhere to the officinal recipes given in the books on medicine, and not introduce innovations, however logical or probable, into the realms of applied or practical Therapeutics.