I was reading on some later Buddhist and Mahayana sutras and kept seeing the principles along the lines of "all phenomenon have no nature of their own and are thus empty." I've studied on scriptures like this before, like the Heart Sutra, but I don't think the Pali Canon or Tripitaka mentions anything about this doctrine. I'm curious what exactly later Buddhists meant by this, and if the Buddha actually taught this doctrine or if Sunyata has basis in the original sutras. Thank you to all.
The Pali phrase in the Suñña Sutta is,
suññam idaṃ attena vā attaniyena vā
... which Wikipedia translates as,
this world is empty of self or anything pertaining to self
Ātman is a Sanskrit word that means inner self or soul. In Hindu philosophy, especially in the Vedanta school of Hinduism, Ātman is the first principle, the true self of an individual beyond identification with phenomena, the essence of an individual. In order to attain liberation, a human being must acquire self-knowledge (atma jnana), which is to realize that one's true self (Ātman) is identical with the transcendent self Brahman.
... which is cognate to (or opposed to, to be contrasted with) the Buddhist Pali term Anatta:
In Buddhism, the term anattā (Pali) or anātman (Sanskrit) refers to the doctrine of "non-self", that there is no unchanging, permanent soul in living beings. It is one of the seven beneficial perceptions in Buddhism, and along with Dukkha (suffering) and Anicca (impermanence), it is one of three Right Understandings about the three marks of existence.
The concept of Anatta or Anatman in Buddhism, is a major difference from the Hindu concept of Atman (self, soul).
Maybe that helps to explain what "self-nature" might mean, or whence it's derived, in "the original sutras".
See also topics which are tagged anatman.
In the Pali, "becoming" is dependently originated. The whole wheel of becoming is about how various things which shouldn't be considered 'self' sustain or feed each other, so I take it that (independent) self-becoming is a paradox, a contradiction, which explains the quote in the OP "all phenomenon have no nature of their own".
If this isn't clear, and/or this appears to contradict other answers, perhaps that's because there are (or there are posited) several categories of self-nature (see e.g. Tri-svabhava-nirdesa).
In the Pāli canon, "sabhāva" is absent from what are generally considered to be the earliest texts.[a] When found in later texts (e.g., the paracanonical Milindapañha), it generically refers to state (of mind), character or truth.
In the post-canonical Abhidhamma literature, sabhāva is used to distinguish an irreducible, dependent, momentary phenomenon (dhamma) from a conventionally constructed object. Thus, a collection of visual and tactile phenomena might be mentally constructed into what is conventionally referred to as a "table"; but, beyond its constituent elements, a construct such as "table" lacks intrinsic existence (sabhāva).
I think that this example (of the non-self of a table) is analogous to the parable of the chariot from the Milinda Panha. Wikipedia dates the Milinda Panha to about 100 CE, which I contrast with the lifetime of the Buddha in about 400 BCE.
The central concept around which all of Nāgārjuna's philosophy is built is the notion of emptiness (śūnyatā). Emptiness is of course always the emptiness of something, and the something Nāgārjuna has in mind here is svabhāva. Different terms have been used to translate this word into English: “inherent existence” and “intrinsic nature” appear etc.
Fwiw Wikipedia says of Svabhava,
In the Mahāyāna Buddhadharma tradition(s) it is one of a suite of terms employed to denote the Buddha-nature
Of what I’ve read and heard of so far, in the scriptures (Sutta-Vinaya – but I’m not in a position to quote) the emphasis on impermanence, or becoming, is not a belief in nothingness. As per the scriptures existence is real, but it is transitory. In the later day Mahayana, it was the later philosopher Nagarjuna, who brought in the concept of sunyata. He argued against the belief that somehow there were ultimate forces or things which had a permanent reality of their own or swabhava as @ChrisW has mentioned. He was not describing sunyata as a void per-se but the present meaning is a later day development. Today some even call Nirvâna as Sunyata, 'emptiness.'. But IMHO if someone or something is there in one place and at the next moment that something or someone is not there any longer, then that place is now ‘Sunyata’ of that person or thing.
Sunnata is from the original Pali scriptures, such as the Suñña Sutta. The definition of 'sunnata' is contained therein, namely, void/empty of self & anything belonging/pertaining to self.
The Ani Sutta states discourses that are words of the Tathagata are deep in their meaning, transcendent, connected with emptiness (suttantānaṃ).
However, from the perspective of the Pali suttas, the intellectual Mahayana quibble about 'sabhava', which also occupies the minds of many an intellectual Theravada, is an extreme view. This quibble is born from intellectual thinking rather than from the clear direct (non-thinking) observation of meditation.
My guess is word 'sabhava' comes from the Theravada commentaries rather than from the Pali suttas. That being said, in my opinion, it does not contradict the Pali teachings of anatta (not-self) & sunnata (emptiness) because as long as 'things' (such as the five aggregates) are clearly seen as 'anatta' (not containing a 'self'); those 'things' remain 'empty'. In other words, there is no need to negate the 'thingness' (or 'sabhava') of 'things' because the word 'sabhava' does not mean 'self', 'ego' or 'personality'.
The Pali scriptures describe form, feeling, perception, fabrications, consciousness, earth, wind, fire, water, space, Nibbana, etc, as having intrinsic qualities, which is essentially the meaning of 'sabhava'. The word 'bhava' can mean 'produce' (rather than 'being') thus 'sabhava' can mean 'self-produced'.
Take, for example, the earth element. What produces/sustains the earth element? I suppose the only logical answer to that question is 'the earth element'. For example, for life forms to sustain the physical body, they must eat other physical life forms. If the earth element is physically broken down, all that is obtained is smaller particles of earth element (atoms, etc).
Therefore, there is no need to quibble over 'sabhava' since, in the experience of meditation, the five aggregates are seen as the 'five aggregates' (rather than as a 'self') and seeing form as 'form', feeling as 'feeling', earth as 'earth', etc, is exactly the same as seeing form as 'empty', feeling as 'empty', etc.
Some Pali quotes below:
And what is the earth property? The earth property can be either internal or external. What is the internal earth property? Anything internal, within oneself, that's hard, solid & sustained [by food]: head hairs, body hairs, nails, teeth, skin, flesh, tendons, bones, bone marrow, kidneys, heart, liver, membranes, spleen, lungs, large intestines, small intestines, contents of the stomach, feces or anything else internal, within oneself, that's hard, solid and sustained: This is called the internal earth property. Now both the internal earth property & the external earth property are simply earth property. And that should be seen as it actually is present with right discernment: 'This is not mine, this is not me, this is not my self.' When one sees it thus as it actually is present with right discernment, one becomes disenchanted with the earth property and makes [craving towards] the earth property fade from the mind.
And why do you call it 'form' ('rupa')? Because it is 'afflicted' ('ruppati'), thus it is called 'form.' Afflicted with what? With cold & heat & hunger & thirst, with the touch of flies, mosquitoes, wind, sun, & reptiles. Because it is afflicted, it is called form.
And why do you call it 'feeling'? Because it feels, thus it is called 'feeling.' What does it feel? It feels pleasure, it feels pain, it feels neither-pleasure-nor-pain. Because it feels, it is called feeling.
And why do you call it 'perception'? Because it perceives, thus it is called 'perception.' What does it perceive? It perceives blue, it perceives yellow, it perceives red, it perceives white. Because it perceives, it is called perception.
And why do you call them 'fabrications'? Because they fabricate fabricated things, thus they are called 'fabrications.' What do they fabricate as a fabricated thing? For the sake of form-ness, they fabricate form as a fabricated thing. For the sake of feeling-ness, they fabricate feeling as a fabricated thing. For the sake of perception-hood... For the sake of fabrication-hood... For the sake of consciousness-hood, they fabricate consciousness as a fabricated thing. Because they fabricate fabricated things, they are called fabrications.
And why do you call it 'consciousness'? Because it cognizes, thus it is called consciousness. What does it cognize? It cognizes what is sour, bitter, pungent, sweet, alkaline, non-alkaline, salty, & unsalty. Because it cognizes, it is called consciousness.