Hinayana Buddhism: Exploring Early Buddhist Schools

After the Buddha’s passing, his teachings did not remain a single, unified system. Over the centuries, Buddhist monks and scholars debated, interpreted, and systematized these teachings, giving rise to a variety of philosophical schools. Among the earliest and most philosophically rigorous were the schools within the Hinayana tradition-a term used in academic contexts to describe the early Buddhist schools that focused on individual liberation. Two of the most important schools within this tradition are the Vaibhasika and the Sautrantika. Together, they laid the groundwork for Buddhist metaphysics and epistemology, influencing not just later Buddhist schools but the entire trajectory of Indian philosophical thought.

What does “Hinayana” actually mean? 🔗

The term “Hinayana” literally translates to “the lesser vehicle.” It was originally used by Mahayana Buddhists to distinguish their own tradition-which emphasized universal liberation-from the earlier schools that focused on individual enlightenment. While the term carries pejorative connotations and is no longer preferred by many scholars and practitioners, it remains widely used in academic philosophy to refer to the early Buddhist schools that arose in the centuries following the Buddha’s death. These schools are also known by several other names: Early Buddhism, Abhidharma Buddhism, Sthaviravada, and Theravada Buddhism, each name highlighting a different aspect of this tradition. The Hinayana tradition is broadly associated with the Sarvastivada school, which flourished throughout North India and Central Asia. Within this larger tradition, the Vaibhasika and Sautrantika emerged as the two dominant philosophical sub-schools, each offering distinct interpretations of reality, knowledge, and the nature of existence.

The Vaibhasika school: direct realism and the reality of all dharmas 🔗

The Vaibhasika school takes its name from the Mahavibhasa (“Great Commentary”), an encyclopaedic Abhidharma text compiled in Kashmir during the Kushan era (roughly 1st-2nd century CE). Followers of this school regarded the Mahavibhasa as the authoritative interpretation of the Buddha’s teachings and built their philosophical system around the ideas contained in it. The school is also referred to as Sarvastivada, a term composed of three Sanskrit words: sarva (all), asti (exists), and vada (doctrine)-meaning “the doctrine that all exists.”

The doctrine of sarvastivada: existence across three times 🔗

The defining philosophical position of the Vaibhasika school is the belief that all dharmas exist in all three times-past, present, and future. In Buddhist philosophy, dharmas are the fundamental building blocks of all phenomenal experience. They are discrete, momentary psycho-physical events that arise and pass away in rapid succession. The Vaibhasikas argued that while dharmas undergo change and transformation, their essential nature (svabhava) persists across temporal states. A past action, for instance, does not simply vanish-its dharmic constituents continue to exist, just in a different mode. Similarly, future dharmas already exist in a latent form, ready to manifest when conditions are right. This is a striking departure from the presentism of other Buddhist schools like the Theravada, which held that only present dharmas are real.

The classification of 75 dharmas 🔗

One of the Vaibhasika school’s most significant contributions to Buddhist philosophy is its systematic classification of reality into 75 types of dharmas. This elaborate taxonomy, which evolved from the work of the scholar Vasumitra, divides all phenomena into five major categories:

Rupa (11 types) covers matter and physical phenomena. Citta (1 type) refers to the bare phenomenon of consciousness itself. Caitasikas (46 types) are mental events or thought-concomitants that accompany consciousness. Cittaviprayuktasamskara (14 types) represents factors dissociated from thought-a category unique to the Vaibhasika school, grouping together experiential events that are neither physical nor mental. Finally, Asamskrta (3 types) are unconditioned dharmas, including space and two forms of cessation. This exhaustive categorization was intended to account for every possible type of conscious experience, providing both a metaphysical map of reality and a practical guide for meditation.

Direct realism in perception 🔗

Epistemologically, the Vaibhasika school advocated for direct realism (bahya-pratyaksha-vada). According to this view, external objects are directly known through perception. When you see a tree, you perceive the tree itself, not a mental copy or representation of it. The senses provide reliable, immediate access to the world as it actually is. The Vaibhasikas accepted two valid means of knowledge: perception (pratyaksha) and inference (anumana). Perception gives us direct contact with reality, while inference allows us to reason about things not immediately present to the senses. This epistemological stance made the Vaibhasika school a form of phenomenalist realism-the world is real, and our senses accurately reveal it to us.

The Sautrantika school: critical realism and extreme momentariness 🔗

The Sautrantika school emerged as a critical response to the Vaibhasika system. The name “Sautrantika” derives from sutranta (scripture), indicating that this school prioritized the Buddha’s original discourses (Sutta Pitaka) over the elaborate Abhidharma commentaries that the Vaibhasikas relied upon. The founding of the school is traditionally attributed to Kumaralata (c. 3rd century CE), and its most famous exponent was Vasubandhu, whose Abhidharmakosa became the most influential Abhidharma text in both Tibetan and East Asian Buddhism. Other notable figures include Srilata (Vasubandhu’s teacher), Harivarman (author of the Tattvasiddhi), and Yasomitra.

Rejection of the three-time existence of dharmas 🔗

The Sautrantikas directly challenged the Vaibhasika doctrine that dharmas exist in all three times. They advocated a position of extreme momentariness (kshanikavada): only the present moment exists. Past dharmas have ceased to be, and future dharmas have not yet come into existence. There is no enduring essence that persists across temporal phases. If everything is constantly changing at the most fundamental level, the Sautrantikas argued, then the idea of permanent, unchanging dharmic essences becomes untenable. Each moment brings genuinely new dharmas into existence, and previous ones simply cease.

This critique also extended to the Vaibhasika’s claim that dharmas undergo change through four distinct characteristics: origination, endurance, decay, and dissolution. The Sautrantikas found the notion of “endurance” particularly problematic. If something is truly changing, they reasoned, it cannot simultaneously endure. Change and persistence are contradictory. Therefore, a dharma exists only for a single instant, performing its causal function in that moment before ceasing entirely.

A simplified classification of dharmas 🔗

While the Vaibhasikas catalogued 75 types of dharmas, the Sautrantikas reduced this number to 43 conditioned dharmas and 2 unconditioned dharmas, totalling 45. They considered the Vaibhasika’s elaborate classification unnecessarily complex and a deviation from the Buddha’s original intent. The 43 conditioned dharmas were organized under the five skandhas (aggregates): form, feeling, perception, mental formations, and consciousness. The two unconditioned dharmas were Nirvana and space. This simplification reflected the Sautrantika commitment to returning to the sutras and avoiding what they saw as the Abhidharma’s over-systematization of reality.

Representationalism in perception 🔗

Perhaps the most philosophically distinctive feature of the Sautrantika school is its theory of perception. Unlike the Vaibhasikas, who held that we directly perceive external objects, the Sautrantikas argued for a form of indirect representationalism (bahyanumeya-vada). According to this view, we never perceive external objects directly. Instead, objects produce mental representations or images (akara) in consciousness, and it is these mental images that we actually experience. The existence of external objects is then inferred from these representations.

The reasoning goes like this: because everything is momentary, by the time a perception is registered in the mind, the external object that caused it has already ceased to exist. What the mind experiences is not the object itself but a mental copy produced through the causal process of perception. As the Encyclopedia of Buddhism notes, this involved positing that cognition involves mental representations of objects rather than direct contact with mind-independent entities. This is why the Sautrantika school is described as advocating critical realism: external objects do exist, but our knowledge of them is always mediated through mental representations.

Dharma theory: the philosophical heart of both schools 🔗

Despite their disagreements, both the Vaibhasika and Sautrantika schools share a commitment to the dharma theory-the project of analyzing all of reality into its most fundamental constituents. According to the Stanford Encyclopedia of Philosophy, the Abhidharma method analyzes conscious experience into constituent mental and physical events called dharmas, and it studies their manifold relationships of causal conditioning. Both schools agree that what we ordinarily take to be stable, enduring objects-a table, a person, a mountain-are actually composed of rapidly arising and ceasing dharmas. The “self” is not a real entity but merely a conventional label applied to a stream of dharmic processes. Both schools affirm the selflessness of persons (pudgala-nairatmya) while maintaining that dharmas themselves possess a kind of intrinsic nature.

Where they differ is on the question of what kind of existence dharmas possess. The Vaibhasikas treat dharmas as real entities (dravya) with intrinsic characteristics that persist across time. The Sautrantikas treat dharmas as momentary, causally efficient events that exist only in the present instant. This disagreement about the ontological status of dharmas became one of the central debates in Buddhist philosophy, and its resolution (or dissolution) by later Mahayana schools-particularly the Madhyamaka and Yogacara-shaped the entire subsequent history of Buddhist thought.

Key differences between Vaibhasika and Sautrantika 🔗

To summarize the core philosophical differences: the Vaibhasika school holds that dharmas exist in past, present, and future, while the Sautrantika school insists that only present dharmas are real. On perception, the Vaibhasikas are direct realists who believe external objects are perceived as they are, whereas the Sautrantikas are representationalists who argue that we only ever experience mental copies of external objects. In terms of dharma classification, the Vaibhasikas enumerate 75 dharmas across five categories, while the Sautrantikas simplify this to 45 dharmas. Regarding scriptural authority, the Vaibhasikas rely heavily on the Abhidharma Pitaka and its commentaries, while the Sautrantikas privilege the Sutta Pitaka-the Buddha’s actual discourses.

The lasting legacy of the early Hinayana schools 🔗

The philosophical contributions of the Vaibhasika and Sautrantika schools extended far beyond the Hinayana tradition itself. The Sautrantika school, in particular, served as a critical bridge to Mahayana philosophy. Vasubandhu, who began as a Sautrantika thinker, later transitioned to the Yogacara school, carrying forward the representationalist epistemology and the doctrine of momentariness into a new framework. The logicians Dignaga and Dharmakirti (5th and 7th centuries CE), who developed the sophisticated Buddhist system of logic and epistemology (pramana-vada), drew heavily on Sautrantika ideas. Their work on the two valid means of knowledge-perception and inference-became foundational for all subsequent Buddhist epistemology and also influenced non-Buddhist Indian philosophical traditions like Nyaya.

The Vaibhasika school’s detailed analysis of dharmas, meanwhile, provided the raw material that later Mahayana philosophers either built upon or deconstructed. Nagarjuna’s Madhyamaka school, for instance, subjected the entire dharma theory to its dialectical critique, arguing that dharmas themselves lack intrinsic nature (svabhava). Without the Vaibhasika system to critique, Nagarjuna’s philosophy of emptiness (sunyata) would not have taken the form it did. In Tibetan Buddhist doxography, the four main philosophical schools are traditionally listed as Vaibhasika, Sautrantika, Yogacara, and Madhyamika-a classification that reflects the enduring importance of these early Hinayana schools as foundational stages in the development of Buddhist thought.

What do you think? If everything we experience is made up of momentary, rapidly changing elements, does anything truly persist from one moment to the next? And does it matter whether we perceive the world directly or only through mental representations-how might that distinction change the way we understand our everyday experience?

References

1. https://en.wikipedia.org/wiki/Mahayana
2. https://en.wikipedia.org/wiki/Sarvastivada
3. https://plato.stanford.edu/entries/abhidharma/
4. https://www.wisdomlib.org/buddhism/essay/buddhism-and-nyaya-study/d/doc1239550.html
5. https://en.wikipedia.org/wiki/Vasubandhu
6. https://en.wikipedia.org/wiki/Sautr%C4%81ntika
7. https://encyclopediaofbuddhism.org/wiki/Sautr%C4%81ntika
8. https://en.wikipedia.org/wiki/Yogachara