A rough-and-ready model like the dosha theory is basically the result of reasoning intuitively – of using rules of thumb to simplify problems for the sake of efficiency. It relies on commonsensical shortcuts that have arisen as handy ways to solve complex cognitive problems rapidly, but at a cost of inaccuracies and misfires.
Truth, when hyped, loses credibility. There have been attempts, of late, to eulogise ancient theories contained in ayurvedic classics as ultra-modern ‘quantum physiology’1. It is, in this context, pertinent to place before the discerning reader a plausible deconstruction of the dosha theory.
The Vedic worldview sees the human body primarily as a nutritive process2. Health and illness, in this commonsensical view, are functions respectively of optimum nutrition and the lack of it. The latter could have two forms – over nutrition and under nutrition. This two-fold classification of illnesses, based on whether they are caused by over nutrition3 or under nutrition, represents the germinal stages of theorisation that finally culminated in the conception of tridosha (three illness-causing factors). This binary classification of illnesses approximated towards itself another Vedic idea of evident practical value – that everything in the universe is composed primarily of agni (fire – the heating principle) and soma (moon – the cooling principle)4. The intellectual infrastructure required for this approximation was readily available in the Vedic philosophical milieu; the Sankhya theory of triguna provided the basic model of triads while the Vaisheshika concept of material properties provided the basis for a systematic classification. The ayurvedic theorists ingeniously employed this infrastructure to create a rough-and-ready model that could systematise their medical experience. Roughly, illnesses due to over nutrition were supposed to be caused by kapha while those due to under nutrition were supposed to be due to vata. These two were ‘cooling’ doshas; to complete the scheme, a third ‘heating’ dosha was required and it was introduced as pitta. Vata, pitta and kapha came to be called the Tridosha.
Meanwhile, the theory witnessed expansion in another interesting line. Once the idea of the two-fold causes of diseases was hypothesised by simple observations, the corresponding idea of two-fold management became a straightforward corollary. All medical treatments could now be classified simply into nourishing measures, meant to treat illnesses caused by under nutrition; and, famishing measures, meant to treat those caused by over nutrition5.
This corollary created the space required for the theory to expand. Illnesses whose causation could not always be explained on the basis of nutrition could now be classified on the basis of therapeutic similarity. Illnesses, in this new paradigm, are again of two types – those that require to be managed by nourishing measures and those others that need famishing ones. In other words, therapeutic similarity replaced pathogenetic similarity as the basis for classifying diseases. The ayurvedic theorists, however, apparently supposed that therapeutic similarity implied pathogenetic similarity. This naive supposition became the basis for the construction of complex pathophysiological conjectures that time and again served as conventionalist stratagems.
A ‘conventionalist stratagem’ is a technique used by a theorist to evade the consequences of a falsifying observation6. One such stratagem is worth discussing; it is excerpted from Charaka Samhita which is the most authoritative of classical ayurvedic treatises –
“What then is the principle of correct treatment? Simply stated, this is to administer measures that are opposed to the properties of the cause and manifestations of diseases. But one must apply reason in every situation. For example, fever is hot, but hot water is often given to the patient, which appears to contravene the basic principle. However, reason tells us that fever originates from the stomach, and the disorders which have their source in the stomach respond to measures that promote digestion. In the present instance, hot water promotes digestion and hence its relevance. However, in fevers associated with fainting and delirium, hot water may be inappropriate“7.
An analysis of this passage is illustrative of the difficulties faced by ayurvedic theorists in balancing fidelity to observed facts with a desire to maintain intact a fundamentally weak theory. That warm water is beneficial in common fevers is a commonly observed fact; but the tridosha theory necessitates the use of a ‘cooling’ measure in the management of an illness characterised by ‘heat’! The theory thus makes a therapeutic prediction that is contrarian to an observed fact. Charaka carefully maintains his fidelity to the observed fact and recommends hot water, but he would not accept the theory falsified. Instead, in an instance of glaring scientific naiveté, he defends the theory by introducing a conventionalist stratagem. He introduces an unobserved conjecture that fever originates in the stomach, and builds on it, to whitewash the theory’s failure. A simple theory, stretched to explain everything, inevitably got enmeshed in a complex web of conjectures.
A rough-and-ready model like the dosha theory is basically the result of reasoning intuitively – of using rules of thumb to simplify problems for the sake of efficiency8. It relies on commonsensical shortcuts that have arisen as handy ways to solve complex cognitive problems rapidly, but at a cost of inaccuracies and misfires. Needless to add, such a model cannot account for observations that are counter-intuitive. The methods of science and statistics grew up precisely to check these obvious limitations of intuitive reasoning. It is time to employ these methods to verify and if possible, to refine this apparently useful theory by sifting its observable elements from the merely conjectural ones. The recent research on the genetic basis of ayurvedic body types is an example of sensible work in this direction9.
Charaka lived two thousand years ago and his scientific naiveté is understandable. He lived, discovered and taught in an era when the scientific method was still nascent. His greatness lies in his spirited advocacy of evidence-based thinking (yukti-vyapashraya). We ought to be grateful to him for the rich repertoire of clinical observations he has left for posterity. Bereft of outdated theories and ideological vestiges, his classic is even today a treasure trove of syndromes and promising prescriptions. The gentleness and holism of his approach are vitally needed in this era of medical aggression and iatrogenic ailments. But his legacy can be preserved and enriched only by those who adore his strengths while being fully aware of his
failures limitations. Being blind to his failures limitations can only lead to arm-chair fantasies with outdated physiological phantoms. Such fantasies can construct ‘phantom physiology’, not ‘quantum physiology’!
- Jayasundar, R. 2009 Quantum Logic in Ayurveda, In Proc First International Conference on Ayurveda, Milan, Italy.
- Taittiriya upanishath, 3-2 annamaya kosha; Bhagavadgita 3-14
- Charaka Samhita, Vimanasthana 3-24
- Rig veda, Mandala 1 Hymn 93; Sushruta Samhita, Sutrasthana 42-7
- Charaka Samhita, Vimanasthana 3 – 41, 42
- Popper, Karl. 1959 The Logic of Scientific Discovery
- Valiathan, M S. 2003 The Legacy of Caraka.154. Orient Longman, Chennai
- Goldacre, B. 2009 Bad Science. Fourth Estate, London
- Periyasamy Govindaraj et al. 2015 Genome-wide analysis correlates ayurveda prakriti, Scientific Reports volume 5, Article number: 15786
G L Krishna is an ayurvedic doctor practising in Bengaluru. He may be contacted at email@example.com
Based on the requests of the author, the following updates have been made to the article.
a) Reference #8 (Bad Science by Goldacre) has been inserted.
b) The word “failures” has been replaced by the word “limitations” at two places in the last paragraph.