Grammatical Proof that Sanskrit was also written
It occurs to me that सूत्रम् – मोऽनुस्वारः (८/३/२३) in अष्टाध्यायी of पाणिनि is concrete evidence that Sanskrit was written, very definitely in पाणिनि’s time, rather, earlier than that also.
I say, earlier than that also, because what पाणिनि composed in अष्टाध्यायी is grammar of Sanskrit, as was already being practised and as had also been detailed by many grammarians before him.
Why I make specific reference to the above सूत्रम् as evidence is because the mention of अनुस्वार in this सूत्रम् is significant only for writing.
A simple example is of the श्लोक in गीता – यं यं वापि स्मरन्भावं त्यजत्यन्ते कलेवरम् । तं तमेवैति कौन्तेय सदा तद्भावभावितः ।।८-६।। Here there are as many as four अनुस्वार-s.
For pronunciation, it makes no difference if the श्लोक is written as यम् यम् वापि स्मरन्भावम् त्यजत्यन्ते कलेवरम् । तम् तमेवैति कौन्तेय सदा तद्भावभावितः ।।८-६।।
Why would then पाणिनि have thought it good or necessary to compose this सूत्रम् – मोऽनुस्वारः (८/३/२३) ?
For a finer observation, it should also be noted that in this श्लोक the word कलेवरम् is written without the अनुस्वार. This is so, because complete interpretation of the सूत्रम् – मोऽनुस्वारः (८/३/२३) has a precursor or a precondition (अनुवृत्ति) ‘हलि’. This अनुवृत्ति requires that there should be हल् i.e. a व्यञ्जनम् after the म्. The word कलेवरम् is at the end of the line. So there is no हल् or व्यञ्जनम् after the म्.
Another evidence, that Sanskrit becomes more charming, when written, comes from writing or not writing the अवग्रह ‘ऽ’.
I got to see a good example in a book of गीता. There the second line in श्लोक १-४४ is shown in two different versions – नरके नियतं वासो भवतीत्यनुशुश्रुम । The optional version is shown as नरकेऽनियतं वासो भवतीत्यनुशुश्रुम । How charming !
नरके नियतं वासो भवतीत्यनुशुश्रुम means, “We heard that there will certainly be relegation to the hell.”
The optional version नरकेऽनियतं वासो भवतीत्यनुशुश्रुम means, “We heard that there will be indefinite relegation to the hell.”
Since the अवग्रह ‘ऽ’ does not get pronounced, the charm of the two versions comes forth, only when written.
There is another instance of this अवग्रह ‘ऽ’ making different interpretations. I learnt about it, when I was studying the biography श्रीसाईसच्चरितम् of Shirdi Sai Baba. Two wholesome chapters 39 and 50 dwell on this.
I would like to take that up as a different discussion.
What I am wanting to put forth is that, mention of अनुस्वार and अवग्रह ‘ऽ’ in अष्टाध्यायी of पाणिनि become concrete evidence, that Sanskrit was written, certainly so during and before पाणिनि i.e. about 400 to 500 BC.
शुभं भवतु !