I read once that Indian philosophy considers four levels of existence:
- being and not being
- not being and being
- not being
I thought this fascinating and more realistic than Western classifications, even if the text did not specify the exact sense of the Indian concepts. I felt that Western concepts such as 'nothingness' are meaningless : 'nothingness' has no referent and should be avoided in reasoning.
Do you happen to know a little more about the issue?