For instance, the original quote "Just because you're paranoid doesn't mean they aren't after you" is significantly more accurate than the paraphrased "It's not paranoia if they really are out to get you,".
The quote is part of a trinity, actually:
1. Even paranoids have enemies.
2. Just because you're paranoid doesn't mean they aren't out to get you.
3. It's not paranoia when they really are out to get you.
If we define the universe as a conspiracy laden place with people out to get Pi specifically he is in fact not paranoid. But delve further into Pi and we learn that he's not always correct, though he is correct more often than you would expect a paranoid person, who is given to delusions, to be.
There's no evidence to indicate Pi believes there is a conspiracy directed at him specifically, though. This has never been shown.
Then again Pibald is clinically paranoid, and takes(or is supposed to take) medicine for that condition. So there is that.
Is he, though? Maybe they're just drugging up him to keep him docile.