paraphrase

• A common thread connecting both extremes of dualism and illusionism is that both assume that phenomenal consciousness is an absolute phenomenon,
  • wherein an object O evinces either property P or ¬P.
• We will show that we need to abandon this assumption.
• The relativistic principle in modern physics posits a universe in which for many properties an object O evinces either property P or ¬P with respect to some observer X.
• In such a situation, there is no one answer to the question of whether object O has property P or not.

question

• how does this argue against the privacy of phenomena?
• it argues against it in the sense that it isn't needed. What is interpreted as private is simply the experience from one relative frame of reference.