The Problem of Universals is one the oldest subjects of debate in Indian philosophy. Realists about universals believe that universals exist in addition to concrete particulars, while nominalists deny the existence of universals. The Nyāya and Mīmāṃsā schools were vocal defenders of realism. Nyāya philosophers believed in universals for a number of reasons:
- Universals explain how different objects share common characteristics. Cow A and Cow B differ from each other in various ways, and yet we recognize that they’re both cows. The Nyāya explanation for this is that what Cow A and Cow B have in common is the universal “cowness” that inheres in both.
- Universals fix the meanings of words. The word “cow” doesn’t just refer to a particular cow, but cows in general. How can a word refer to many different objects at once? The Nyāya solution is that the word “cow” refers to a particular qualified by the universal cowness, which is present in all individual cows.
- Universals are a solution to the Problem of Induction, first raised by the Cārvāka empiricists. Nyāya philosophers viewed the laws of nature as relations between universals. Our knowledge of these universals and the relations between them justifies inductive generalizations, and consequently, inferences such as the presence of fire from the presence of smoke.
Buddhists were the best-known nominalists in the Indian philosophical tradition. The Buddhist hostility towards universals is perhaps best expressed by Paṇḍita Aśoka (9th century): “One can clearly see five fingers in one’s own hand. One who commits himself to a sixth general entity fingerhood, side by side with the five fingers, might as well postulate horns on top of his head.”¹
In this post, I will briefly go over how Buddhists responded to the first two reasons for believing in universals provided by the Nyāya school. The Buddhist defense of induction will have to be the subject of a separate essay.
The form of nominalism Buddhists advocated is called apoha, the Sanskrit word for “exclusion.” The first precise statement of apoha nominalism can be found in the works of Dignāga (6th century). Dignāga claimed that the word “cow” simply means “not non-cow.” Since there is obviously no universal “not cow-ness” present in every object that is not a cow, this semantic view doesn’t commit us to the existence of universals. Every cow is a unique particular distinct from all other objects. We simply overlook the mutual differences between cows and group them together based on how they’re different from non-cows. Thus, it’s not because cows share something in common that we call them by the same name. Rather, we think all cows share something in common because we have learned to call them by the same name.
There are some objections that immediately spring to mind, and Nyāya and Mīmāṃsā philosophers brought them up repeatedly in their criticisms of apoha nominalism. First, how does saying that “cow” means “not non-cow” provide a solution to the problem of universals? “Not non-cow” involves a double negation, so to say “cow” means “not non-cow” is just to say “cow” means “cow.” This leads us right back to where we started, and just as before, it seems that we need to posit a universal cowness. Second, how can we focus on cows’ common differences from non-cows unless we already know how to tell what a cow is in the first place? Once again, we seem to have gone in a circle, and apoha seems to presuppose precisely what it was supposed to explain.
Dignāga’s successors responded to the first objection by drawing distinctions between different kinds of negation. Consider the statement: “This is not impolite.” Now, at first glance it might seem like this just translates to “This is polite,” because of the double negation involved in “not impolite.” But this is not necessarily the case. The statement could be about something to which the very category of politeness does not apply, in which case “not impolite” is distinct from “polite.” Thus, “not non-cow” can mean something genuinely different from “cow.”
To understand how Buddhists responded to the second charge of circularity, it helps to look at another Buddhist view. Buddhists were mereological reductionists: they did not believe that wholes were anything over and above their parts. So, a table, for instance, is nothing more than its parts arranged table-wise. The “table” is just a conceptual fiction: a convenient designator we use because of our shared interests and social conventions. It is conceivable, for instance, that someone who has never seen or heard of tables before will not see a table, just pieces of wood put together in seemingly random fashion. The idea that the table is ultimately real arises when we project our interests on to the world. How is any of this relevant to the question of universals? Buddhist philosophers argued that something similar goes on when we fall under the impression that all cows share a common cowness. We overlook the differences between individual cows because they satisfy some of our desires – for example, the desire for milk – that non-cows don’t. We then project our interests on to the world, mistakenly concluding that cowness is a real thing.
This may not seem like a very satisfactory response. It just pushes the problem back a step. How do all these particulars satisfy the same desire if they don’t share something in common? In this case, it seems like the cows really do share something: the ability to satisfy our desire for milk. Dharmakīrti (7th century) responded to this by using the example of fever-reducing herbs. He pointed out that there are many different herbs that reduce fevers. But it would be foolish to conclude from this that there exists a universal “fever-reducing-ness.” Each of these herbs is different, and they don’t reduce fevers in the same way, or use the same mechanisms to do so. We group them together under a single category only because of our subjective interest in reducing fevers. Dharmakīrti’s claim is that the same is true of everything. Each particular serves our interests in a manner that’s utterly distinct from everything else in the world. And so once again, there is no need to posit universals.
But there are still some lingering worries here. While we may accept that in the case of the herbs there is no universal fever-reducing-ness, does the same response work for simple substances such as elementary particles? Assuming for the sake of argument that an electron is an elementary particle, surely all electrons share something in common. Doesn’t the ability to bring about similar effects require a shared capacity – in this case, the same set of causal powers? One possible response to this line of argument, formulated by the philosopher Kamalaśīla (8th century), is to adopt what we would recognize as a Humean view of causation. Kamalaśīla rejected the notion of causal powers entirely, and like Hume, stated that there is nothing more to causation than constant conjunctions of events. Once again, talk of “causal powers” is just a convenient way of speaking about certain correlations that we never fail to observe.
This is obviously a very brief sketch of apoha nominalism. There is much more to say, particularly on the subtle differences between different versions of apoha defended by different Buddhist philosophers. This is a good place to start for further reading.
 From the translation in Apoha: Buddhist Nominalism and Human Cognition, edited by Mark Siderits, Tom Tillemans and Arindam Chakrabarti (2011).