If you Google the word 'myth' the following two meanings show up:
a traditional story, especially one concerning the early history of a people or explaining some natural or social phenomenon, and typically involving supernatural beings or events.
a widely held but false belief or idea.
I think when they say the great epics Ramayana and Mahabharata (or from other beliefs) are myths, they are actually referring to the former definition, rather than the latter. But because the latter is more widely used and popular, it is often interpreted that way, which is not true.
One statement, if History gets old it becomes Legend and when Legend gets old, it becomes a Myth.
In short, they are too old to get proofs from, and they are repeated so many times, that we even cannot be sure that each and every part of them is correct (I am not saying false, history can also be told in some modified form).
Mahabharata was about 3200 BC and we don't know much things, for example, Indus Valley Civilization which is younger; around 2300 BC.
The advancement of science has got many proofs of Mahabharata but Ramayana still remains a myth, for many minded humans.
In this age(Kali Yuga) the spiritual connection to the ancestors/pitris has been broken for the past five hundred years or so. Ever since the awakening of materialistic philosophies this problem has arisen and prolonged foreign rule has compounded matters. We have allowed foreigners to tell us how our past should be perceived. During the time of Chandragupta Maurya Megasthenes in his work Indica (Indica)
refers to conversation in the royal court how people refer to so many years since the passing of Krishna. So this would imply that the passing away of Krishna was not a mere mythological story but was held as a milestone in real time.
Mind you in any authentic Guru/parampara tradition still active today considering these stories as myths would be considered as blasphemy. Outside that where the influence of Dharma(spiritual law) fluctuates these are propagated as myths.
I would have a look at who started using the word 'Mythology' to describe Hindu epics. Or more specifically, the question would become "Who first described Hindu religion in English language?"
What are the kind of cultural biases/nuances held by the people who described Hinduism to the European world? Were they affiliated to another religious system which treats 'non-believers' in a negative light? Does association with an Abrahamic religion influence your attitude towards people of non-Abrahamic religions?
What was the nature of interaction between English and India when Hinduism was explored by English? Was it an equal-to-equal relationship or a ruler-ruled one? What kind of views did other Abrahamic religionists have towards heathens?
Do they call their own religious texts as Mythology? Would one hear a Christian or a Muslim referring his/her respective theology as 'Christian/ Islamic mythology'?
Would the guardians/speakers of the language be obligated to modify the terminology when there is no real opposition to it? Would the word 'negro' be outlawed if Blacks didn't fight for it?
Just thinking about these questions answers most of the original question. There is no reason to rubbish one particular religion's self-described timeline as mythology when the same is not applicable to one's own.
TLDR => The basic reason behind calling Hindu epics as 'myths' is the inherent bias of the translators.
There are myths in every culture.The meaning of myth as unverifiable, untruthful folklore stories has no relevance in contemporary Hinduism.
The ancient Hindu land has the Ramayana and Mahabharata as guiding scriptures, they will live on as vibrant moralizing instruments of cultural and social changing forces in modern times too with ever- increasing relevance.
In my opinion, the words myth or mythology are used to denigrate and caste a strong doubt on our own history. Also, many Hindus do the same. The reasons for which I imagine are: fear, confusion about our own origins, shame, leftover intellectual colonization by the British, brainwashing by the Judeo-Christian thoughts or all of these.
I would like to support my opinions by providing the definition of these two words.
A myth is defined by Merriam-Webster dictionary as
an idea or story that is believed by many people but that is not true
The Merriam-Webster dictionary definesmythology as such
the myths of a particular group or culture
ideas that are believed by many people but that are not true
Hence, any use of the word mythology instead of history (especially in cases where events have proven to be historical accounts) comes from a questionable intent.
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