I think there is reasonable - but no way conclusive - evidence that the Pali Canon is essentially unchanged from the time when the monks memorized it after Buddha died.
And back then in a culture without writing there was great importance placed on memorization. The Brahmins were able to memorize the Vedas. So why not the Buddhists memorize the Pali Canon? There are modern monks who have memorized the entire many thousands of pages of the canon and can recite it from any point word perfect. So no reason why that shouldn't have been the case then also.
There's also lots of internal evidence that the canon consistently describes India as we understand it was at the time of the Buddha. A place without writing, many small countries, and for them, South India and Sri Lanka were unknown. So - if it was invented later I think it passes belief that they would have invented all those sutras and never mentioned writing, or Sri Lanka or S. India and consistently described the political and technological situation as it was around the time of the Buddha.
So - if the Pali canon is indeed authentic, then we know rather a lot about the Buddha. The monks started memorizing the sutras while he was still alive but relatively late, just a few years before he died (they did this because the leader of the Jains had died recently and his followers were unclear about some of the details and disputed them after he died - so they wanted to make sure the same didn't happen for the Buddha's teachings).
Which is not to say it is an accurate historical record in the modern sense. First of all the Buddha by then was getting on for 80, so the stories about his youth are about events that happened half a century earlier or nearly 80 years earlier in case of his birth. Also they hadn't yet invented modern maths and experimental science, and had a world view quite a bit different to us. So what seemed quite normal to them seem magical and strange sometimes to us. And their main aim was to present his teachings clearly.
But - I think what we have are, quite possibly the memories of some of the details of the Buddha's childhood and youth. But not in the sense that he literally first encountered an old person or a sick person for the very first time after he got married - that is surely a simplification of what actually happened - but - a way of telling the story that is easy to remember and striking. His later teachings and the events of his death, I'd imagine are probably presented pretty accurately bearing in mind that of course they were also adapted for memorization so not that he taught word for word like that.
Some of the things are confirmed by archaeology also.
But - this is just one view. Some scholars think this. Others think that only a few words and a few teachings in the Pali Canon date back to the Buddha and rest was added later. Others remain agnostic about whether they are authentic or not.
So in short, nobody really knows. I think most are in agreement there was a historical Buddha. But some variation in views about what he actually taught and how much we know about his life.
This is my blog post where I talk a bit about some of the findings of scholars, which is definitely biased towards my own views that the Pali Canon is authentic, I say so
Origins of the Buddhist Sutras - were they the Teachings of the Buddha? by Robert Walker on Some ideas about Buddhist teachings
For an overview of range of opinions of scholars:
Pāli Canon#Sources
Anyway - since he died before the introduction of writing to India, then most of what we know is from the memorized teachings in the Pali Canon. So it depends really on how authentic you think those are - whether they represent the words of the Buddha and describe his life, or were written later. Some were written later, everyone agrees, but there is a very substantial core of sutras in the Pali Canon that may, possibly, date right back to soon after the Buddha died, and if so we know a fair bit about him.
And back then in a culture without writing there was great importance placed on memorization. The Brahmins were able to memorize the Vedas. So why not the Buddhists memorize the Pali Canon? There are modern monks who have memorized the entire many thousands of pages of the canon and can recite it from any point word perfect. So no reason why that shouldn't have been the case then also.
There's also lots of internal evidence that the canon consistently describes India as we understand it was at the time of the Buddha. A place without writing, many small countries, and for them, South India and Sri Lanka were unknown. So - if it was invented later I think it passes belief that they would have invented all those sutras and never mentioned writing, or Sri Lanka or S. India and consistently described the political and technological situation as it was around the time of the Buddha.
So - if the Pali canon is indeed authentic, then we know rather a lot about the Buddha. The monks started memorizing the sutras while he was still alive but relatively late, just a few years before he died (they did this because the leader of the Jains had died recently and his followers were unclear about some of the details and disputed them after he died - so they wanted to make sure the same didn't happen for the Buddha's teachings).
Which is not to say it is an accurate historical record in the modern sense. First of all the Buddha by then was getting on for 80, so the stories about his youth are about events that happened half a century earlier or nearly 80 years earlier in case of his birth. Also they hadn't yet invented modern maths and experimental science, and had a world view quite a bit different to us. So what seemed quite normal to them seem magical and strange sometimes to us. And their main aim was to present his teachings clearly.
But - I think what we have are, quite possibly the memories of some of the details of the Buddha's childhood and youth. But not in the sense that he literally first encountered an old person or a sick person for the very first time after he got married - that is surely a simplification of what actually happened - but - a way of telling the story that is easy to remember and striking. His later teachings and the events of his death, I'd imagine are probably presented pretty accurately bearing in mind that of course they were also adapted for memorization so not that he taught word for word like that.
Some of the things are confirmed by archaeology also.
But - this is just one view. Some scholars think this. Others think that only a few words and a few teachings in the Pali Canon date back to the Buddha and rest was added later. Others remain agnostic about whether they are authentic or not.
So in short, nobody really knows. I think most are in agreement there was a historical Buddha. But some variation in views about what he actually taught and how much we know about his life.
This is my blog post where I talk a bit about some of the findings of scholars, which is definitely biased towards my own views that the Pali Canon is authentic, I say so
Origins of the Buddhist Sutras - were they the Teachings of the Buddha? by Robert Walker on Some ideas about Buddhist teachings
For an overview of range of opinions of scholars:
Pāli Canon#Sources
Anyway - since he died before the introduction of writing to India, then most of what we know is from the memorized teachings in the Pali Canon. So it depends really on how authentic you think those are - whether they represent the words of the Buddha and describe his life, or were written later. Some were written later, everyone agrees, but there is a very substantial core of sutras in the Pali Canon that may, possibly, date right back to soon after the Buddha died, and if so we know a fair bit about him.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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