Hari Om. Thank you very much for the explanation, this is very helpful in clearing up my doubt.
Re: example of glass with water / air, please allow me to explain further. Both water and air are transparent. Consider water as Self. A glass full of water (Self) = empty of air (Sunya). Or a glass empty of water (Sunya) = full of air (Purnam = Self). What is Sunya in one, is Purnam in another, and vice versa. Looking from outside, the glass appears to be empty because of the transparency of the content (air / water). So the Buddhists would assert voidness (empty of air / water = Sunya). And the Vedantins would assert to look deeper (full of air / water = Purnam).
