In these excerpts from a paper by G N Ramachandran, the author explains the significance of Indian multivalued logic to epistemological issues which release the seeker from the absolutism of Aristotlean binary logic.
In these excerpts from a paper by G N Ramachandran, the author explains the significance of Indian multivalued logic to epistemological issues which release the seeker from the absolutism of Aristotlean binary logic.
Logic in India was not solely the subject matter of ‘grammar’ of reasoning, but a more lively one of the techniques of argument and discussion. Yet some very recondite aspects of multivalued logic developed in this century are not only evident but are explicitly stated in ancient Indian philosophy. Thus, syad-vada, the doctrine of doubt, envisages two new states of truth, namely doubtful and impossible, in addition to truth and falsehood respectively.
An even finer subdivision of truth is made in sapta-bhangi into seven truth values, postulated by Jaina philosophers. In Nyaya philosophy also, logic is conceived of as dealing essentially with the removal of doubt.
As is well-known, epistemology is the science of the theory of knowledge. Since this encompasses the whole of science, philosophy and religion, we shall only discuss some general features of the processes of obtaining knowledge, and of applying it, for which purpose, very precise and broad-based concepts had been developed in ancient Indian philosophy.
In discussing how knowledge is obtained, we shall also ask questions which are partly religious in nature, such as “What is the basis of existence?” “What force drives the Universe?” “Is what we see, hear and feel, the real nature of things, or are they only a partial picture of these as seen by human perception?” In doing this, the first consideration is the question of methods of gaining knowledge. It consists of three parts, of observation, inference and codification. Of these inference is the most significant one and requires essentially the operation of the human mind. Actually, the process of inference as considered in classical Indian logic, requires both semantics and logic, which are clearly distinguished in modern philosophy.
Having considered the ways in which knowledge is acquired, the more interesting question as to whether the human mind will be capable of exploring and understanding the whole of existence, which can be equalized to the modern idea of “nature”, becomes significant. Here, Hindu philosophy has a very simple answer, viz., that man is part of nature and the laws governing nature are also the laws governing his thought processes.
Hence, if there is a directing force which covers all of existence, then all of it is, in principle, understandable by the human mind. The question whether this force is a person in the form of “God” who oversees everything, or a force, or a power, called “nature” which is the root cause of all order in things, is not material to Hindu philosophy. Both concepts are freely used and they may be technically termed as ‘monotheism’ and ‘monism’.
These considerations lead to a very simple synthesis of religion and science, in ancient Indian culture. One is not, in any way, contradictory to the other. It is perfectly possible to be a true scientist and believe in the scientific method of exploration of nature and, at the same time, accept the existence of a universal power that encompasses all these and directs it. We shall consider first the relevant aspects of Indian logic with special reference to the concept of “Syadvada”, or the “principle of indeterminacy”.
Logic in Ancient India and Modern Times
The science of discussion is known as Nyayashastra. But Nyaya means much more than pure logic which is defined as the “grammar” of an argument in the modern sense. In fact, Nyaya encompasses the whole process of reasoning- both its grammar (logic) and its veracity (semantics). The word ‘Nyaya’ in its dictionary sense signifies the concept of “right” or “justice”. Therefore, the discipline of Nyayashastra is the science of right judgment or true reasoning. In the classical example of an argument, analogous to a syllogism, in the Nyaya system, the argument has five parts – (a) “proposition” based on verbal testimony, (b) “reason” based on inference, (c) “example” based on perception, (d) “application” based on comparison, and finally (e) a “conclusion” based on all the above four steps. In view of this, classical Indian logic did not make a detailed analytical examination of the rules of logic, but rather applied itself to a study of types of argument required for special situations. However, in doing this, it has produced some exceptionally beautiful approaches which do not appear to have been developed in modern logic except in the 20th century.
We shall comment on two specific aspects which are only vaguely conceived of in Nyaya, but which are explicitly studied and discussed in Jaina philosophy (and which have been followed up by the author in a rigorous mathematical way, and has led to a theory of multivalued logic in general), viz. syad-vada and saptabhangi.
Syad-vada
This is based on the most conspicuous of the doctrines of Jaina philosophy, namely that the conception of reality is inherently indeterminate and can only be based on knowledge that is syad, meaning ‘may be’. According to it, nothing can be understood completely and the nature of our knowledge about anything – be it material, intellectual or spiritual – can always only be partial and limited. The answer to the question, ‘Is this true?’ about anything, can in the ultimate sense be answered only as ‘may be true or may not be true’. This may look very puzzling at first. However, if it is understood that what is known about anything at a given time is only based on the knowledge which is ultimately what is available at that time, and that new knowledge may give a different picture, then the concept of universal doubt becomes obvious and reasonable. For example, Newton’s Laws of Motion were taken to be the absolute basis for physics, and a nineteenth century scientist would have answered the question, “Are Newton’s Laws absolutely valid?” by a firm definite ‘yes’. But twentieth century physics found it necessary to modify it, and replace it by Einstein’s equations. In fact, nobody can say, even now, that
Einstein’s equations are the last word, because newer observations and theories can make still further changes in them. In this sense, any theory (or any knowledge) derived from necessarily limited, incomplete, observation of facts, can never be absolutely true.
This purely philosophical concept, which is obviously a very valid one in epistemology, was put in a practical form by the Jaina philosophers. Thus, in addition to two states of truth, ‘yes’ and ‘no’ of standard logic, two more alternatives were added, namely ‘yes and no’ and ‘neither yes nor no’. Of these, the former means that the answer to the question “Is it true?” can be either yes or no, with both possibilities being present, so that the question is still unanswered, or unanswerable. The answer to the question is then said to be in the state ‘syad’ or ‘may be’. On the other hand, the latter (neither yes or no) means that neither of the possibilities ‘yes’ and ‘no’ is the correct answer, so that it signifies the impossibility of the statement, and hence the contradiction of the argument.
The state of ‘syad’, viz., ‘may be true or may be false’, is not at all a strange state of truth for it is being applied by everybody almost every day. The simple answer ‘no comment’ to a question means, in effect, that the answer is ‘may be yes or may be no’, so that the fact in question has the state ‘syad’. Even in mathematics, the formulation of the proof of a theorem, or the disproof there of, leads one from a state of indefinite knowledge about the theorem to definite knowledge that the theorem is true or false. It is very much to the credit of the Jaina philosophers that they gave explicit mention of such a state of truth.
Acquisition of Knowledge
The above ideas that everything is syad to start with, and that the acquisition of knowledge consists of the removal of doubt and the creation of definiteness, are found even in the Upanishads.
Thus, the classical hymn “asato ma sad gamaya” which means lead me from absence (of knowledge, i.e., ignorance) to presence (i.e., enlightenment),’ contains in itself the essence of epistemology, viz., that the acquisition of knowledge consists of the removal of doubt.
In fact, even with reference to the science of Nyaya, Vatsyayana says as follows: ‘tatra nanupalabdhe no nirnite-arthe nyayah kim tarhi samayite-arthe,’ This means ‘logic functions neither with regard to things known to be false, nor with regard to things known to be definitely true, but it functions only with regard to the things that are doubtful.’ Thus Indian logic deals with the whole field of epistemology in general, viz., methods of clearing ignorance, or doubt, and obtaining definite information, or knowledge.
However, this is not the whole story, for Jaina philosophy has gone further and given a description of even more subtle subdivisions of the states of truth than those obtained in syad-vada as mentioned above.
Indefinite States in Sapta-bhangi
The doubt in the above examples arose essentially because of lack of precise knowledge as to the truth or falsity of the statement. But this is not necessarily the case. It is quite possible that the proposition itself is neither capable of being shown to be true nor of being shown to be false, i.e., the syad state is inherent in the statement of the proposition under consideration. This was also conceived of by the Jains. In fact, they ‘went further and stated that the nature of knowledge has a sevenfold division, which may be stated as follows.
- May be, is (Syad asti).
- May be, is not (Syad nasti).
- May be, is inexpressible (Syad avaktavyah).
- May be, is and is not (Syad asti nasti).
- May be, is and is inexpressible (Syad asti ca avaktavyah).
- May be, is not and is inexpressible (Syad nasti ca avaktavyah).
- May be, is, is not and is inexpressible (Syad asti ca nasti ca avaktavyah).
This formulation which is called sapta-bhangi is an even more precise classification of states of truth than syad-vada.
It will be noticed that just as syad-vada is obtained by making all possible combinations of two elements asti (is) and nasti (is not), sapta-bhangi contains various combinations of three elements, namely asti (is), nasti (is not) and avaktavyah (inexpressible). The very word ‘inexpressible’, expresses the fact that it requires careful examination to obtain its full significance. It is a modification of the doubtful state of syad-vada, in which the definite states ‘yes’ and ‘no’ are both removed and yet something remains which is a truth value. The best way of appreciating the existence of such a state of truth is by taking an example.
Suppose we ask the question, “Is it true that if X is an integer then it is a prime?” the answer is ‘not always, not never, but sometimes.’ In the framework of sapta-bhangi, ‘always true’ is asti, ‘never true’ is nasti, ‘sometimes true but neither always and neither never’ is avaktavyah.
Description of the ‘Infinite’ Via Paradoxes
There is a close analogy of these ideas of modern logical analysis with the concepts in Indian philosophy of the ‘Infinite’ (ananta) which is one of the attributes of Brahman (absolute Reality). The Upanishads contain many statements to the effect that this Reality has contradictory properties such as
It is both larger than itself and smaller than itself (anorniyan mahato mahiyan); We can take the whole of it away from it, and what remains is still the whole of it (purnasya purnamadaya
purnamevavasisyate); If you think you know it, then you do not know it; if you think you cannot know it, then you know it (yasyamatam tasya matam, matam yasya n veda sah; avijnatam vijnatam, vijnatam avijnatam)
Because it is something that transcends reason, the ultimate reality, brahman, is describable only
by such contradictory statements, and it is something that stands by itself outside all existence and yet at the same time, it permeates all of existence.
The logical similarity to the example of infinity in mathematics is very close. In the case of mathematical infinity, we have to say that although it is a number, it does not belong to the class of finite numbers, and therefore it can have contradictory properties such as being both greater than and smaller than itself.
Excerpted from “Vedanta and Modern Epistemology-G N Ramachndran” from the collection Perspectives of Sankara.(1989)
The author, Prof G.N. Ramachandran, (8 October 1922 – 7 April 2001) is widely acknowledged as one of the most important Indian scientists of the 20th century. He was the first to propose a triple-helical model for the structure of collagen. He also made other major contributions in biology and physics. He was honoured with fellowships of numerous scientific bodies including the Royal Society, UK.
Further reading:
- The Indian-Jaina Dialectic of Syadvada in Relation to Probability by P.C. Mahalanobis, Dialectica 8, 1954, 95–111.
- The Syadvada System of Predication by J. B. S. Haldane, Sankhya 18, 195–200, 1957.