Re:
Saizhan.
I've plundered pretty much every mystical tradition that exists for my campaign, so you'll find bits of many cropping up.
Saizhan is based primarily on Buddhist Madhyamika, though.
The dialectic of negation certainly isn't mine - a 2nd century philosopher called Nagarjuna systematized it, and it was further refined by Candrakirti. The original basis is a series of four questions - the
catuskoti - said to have been posed to the Buddha:
1) Whether the world is eternal, or no, or both, or neither.
2) Whether the world is finite, or infinite, or both, or neither.
3) Whether the Buddha exists after death, or not, or both, or neither.
4) Is the soul identical to the body, or different from it?
The Buddha refused to answer the questions, because any categorical statement would deny the possibilty of the other theses. This was 2000 years before Kant's antinomies, btw.
Point 3) is the one of most interest - the ens/non-ens question. In the SH this is the basis of the Ontological Paradox - note that the RL term 'Ontological Paradox' when used by Western philosophers has different connotations.
It seemed an interesting idea to superimpose basically Eastern philosophies (together with the accompanying idea that multiple truths are possible) onto an entrenched Western social model (with monotheism), and see what happened when players interacted with it.
This picture is much more important, however, and provided more inspiration than any philosophy.