# Ratnakīrti

Ratnakīrti (11th century CE) was an Indian Buddhist philosopher of the Yogācāra and epistemological (pramāṇavāda) schools who wrote on logic, philosophy of mind and epistemology. Ratnakīrti studied at the Vikramaśīla monastery in modern-day Bihar. He was a pupil of Jñānaśrīmitra, and Ratnakīrti refers to Jñānaśrīmitra in his work as his guru with phrases such as yad āhur guravaḥ.
Ratnakīrti's work has been termed as "more concise and logical though not so poetical" compared to that of his teacher, although he does build on much of Jñānaśrīmitra's work.

## Life

Ratnakīrti was active sometime between 1000 and 1050 CE. Among his contemporaries at Vikramashila were Ratnākaraśānti and Jñanasrimitra. Ratnakīrti engaged with both of them on an intellectual level and it is clear that Ratnakīrti was Jñānaśrīmitra's student on subjects relating to logico-epistemological topics as the former often quotes the latter as his "guru".
With Ratnākaraśānti, the relationship was more complex as it is likely that Ratnakīrti was his pupil on topics related to tantra however Yuichi Kajiyama states that "Ratnākaraśānti learned Buddhism, exoteric and esoteric, under Ratnakīrti and others."

## Philosophy
### The problem of other minds

Ratnakīrti's "Refutation of Other mindstreams" (Santānāntaradūṣaṇa) argued that knowledge of external streams of consciousness (citta-santāna) is a form of inference (anumāna) and not direct perception (pratyakṣa). Ratnakīrti introduced the two truths doctrine as key to the nature of the discussion. Since inference deals with conceptual universals, the proof of the mindstreams of others, while empirically valid in relative truth (saṃvṛtisatya), does not hold ultimate metaphysical certainty in absolute truth (paramārthasatya). Ratnakīrti, therefore, argued that at the ultimate level, there is only an undifferentiated non-dual consciousness (vijñānādvaita) since one cannot differentiate consciousness as a whole into different individual minds.
Ratnakīrti states:
   If one’s own mind is distinct from another by nature, it should appear together with a limiting object (avadhi) [i.e. another mind]. Nor should it be apprehended that [one’s own mind] is identical with [another mind].
This means that any knowledge of a distinction between two things depends on perceiving two things (and seeing how they are different). However, we can only know our mind directly through perception. Therefore, one’s mind cannot be shown to be distinct from other minds, but they also cannot be shown to be identical, since this knowledge would be based on perceiving them as well.
According to Jan Westerhoff, the main point of Ratnakīrti's argument can be summarized as follows:
   His key point is that mental events that occur in our mind do not specifically identify themselves as belonging to our own mental stream. The simple reflexivity of consciousness, which the Yogācārins accept, is not enough here. Neither consciousness being aware of itself, nor the fact that I consider my thoughts to be mine, is sufficient for making them mine; there needs to be some internal way of identifying them as mine and as not belonging to somebody else. Simply thinking of a thought that is mine will not be sufficient since another person will think the very same thing of their thought, and this will be theirs, not ours. Therefore, We would need a unique way of connecting each set of mental events with some unique identifier, like ‘JCW’s thought’, to regard them as mine. This kind of thought-tagging cannot just boil down to belonging to a specific set of mental events forming a maximally connected series, the standard Buddhist reductionist account of a person. This would not rule out solipsism, since if solipsism was true my thoughts would obviously belong to such a series, which would be the only one there is. Rather, the ‘JCW’ tag of each thought would need to be internally accessible, and distinguishable from the ‘ABC’ tag, the ‘DEF’ tag, and so on. But such branding of thoughts in terms of irreducibly distinct persons that have them is of course not possible within the Buddhist conception of the mind. If we are reductionists about persons, it seems, then we have to accept the consequence that we cannot really differentiate between different streams of consciousness.
Thus, Ratnakīrti argued that from an ultimate point of view, not only do the distinctions between a subject and object, disappear, but also distinctions between any and all individual subjects. Ratnakīrti's theory sees no logical foundation for individuating mindstreams, and so there are no boundaries between minds from the perspective of ultimate truth. Since this non-duality of mind only applies at the level of ultimate truth, Ratnakīrti does not think this invalidates the Mahayana path which is based on compassion for all beings (who do exist at the level of conventional truth as impermanent phenomena).
Furthermore, Ratnakīrti only argues that other mindstreams cannot be proven. He does not argue that one can prove the non-existence of other minds. He only disproves the possibility of inferring distinctions among minds.
Ratnakīrti's monistic interpretation of Yogācāra is known as the Citrādvaitavāda school (the view of variegated non-duality) or Vijñānādvaitavāda school (the view of non-dual consciousness).

### The ultimate existence

Ratnakīrti elaborates his concept of ultimate reality further in his “Debating Multifaceted Nonduality” (Citrādvaitaprakāśavāda). The ultimate reality is the direct object of perception, the only object of consciousness which is not associated with mental construction (vikalpa). It is what is consciously manifested (prakāśa) in awareness and what is directly known by awareness. According to Ratnakīrti's Citrādvaitaprakāśavāda, whatever is manifest to awareness is one single (eka), nondual (advaita) image. Ratnakīrti further argues that this image is a complex, multifaceted and dynamic reality. Thus, it contains within it many sub-images or aspects, such as colors, tastes, and so on (covering all possible qualias). Thus it is a multifaceted nonduality (citradvaita), a single image with a myriad number of aspects. This image is also reflexively self-aware and is thus not different from awareness or consciousness.
Thus, for Ratnakīrti, at the level of ultimate truth, there is nothing but a single multifaceted image which also includes self-awareness (svasamvedana). This is the only thing that truly exists at the ultimate level of reality. This is the single ground of all individuation and conceptual constructions (out of which the individual mindstreams and myriad mental experiences are constructed). All other objects that are not this non-dual self-aware manifestation (such as persons, universals, concepts, the external world etc) can only be conventionally real (samvrti).

### Other views

Ratnakīrti's "Refutation of Arguments Establishing Īśvara" (Īśvarasādhanadūṣaṇa) argued against the Hindu concept of a creator God. He wrote that it is not possible to establish Īśvara through inference as the Naiyāyikas did. The text begins with an explanation of the Nyāya belief system, followed by a criticism of inferences that establish an intelligent creator.
Ratnakīrti's "Proof of Exclusion" (Apohasiddhi) establishes a theory of exclusion that follows Dignāga's theory of the same. It explains how thoughts and perception become understood through inference, and it is a theory of definitions and meaning-making. There are three types of exclusion described in the text.

## Works

Works attributed to Ratnakīrti include:
* Apohasiddhi - This text focuses on the key theory of exclusion (apoha) and defends his views on it from critics
* Īśvarasādhanadūṣaṇa - This work critiques theories of a singular creator deity, which Hindu thinkers call Īśvara.
* Kṣaṇabhaṅgasiddhi (Proving momentariness) - Defends the theory of momentariness, the view that all dharmas (phenomena) last only for a moment.
* Citrādvaitaprakāśavāda - The non-dual mind manifests awareness variously. This awareness takes the form of a single image, and the various aspects of the image comprise perception.
* Pramāṇāntarbhāvaprakaraṇa - A work on epistemology (pramana)
* Vyāptinirṇaya - Inspired by the Vyāpticarcā of Jñānaśrīmitra, it clarifies the main ideas about the limits of logical pervasion (vyāpti).
* Santānāntaradūṣaṇa (Refutation of Other mindstreams)
* Sarvajñasiddhi (Perfection of knowledge)
* Sthirasiddhidūṣaṇa - A refutation of the idea that dharmas endure for longer than a moment
* Udayanīrakaranam
The works are compiled in Ratnakīrtinibandhāvali.