I will endeavor to answer the question.
* The world is real.
* Science is only as flawed as the humans attempting to apply it (or interpret it) in the study or research of the world.
That said, humans have been known to view or perceive things in a manner that is not true (nor even remotely close to reality), so in a manner of speaking, for them the world is an illusion.
Examples:
a. A young fellow falls head-over-heels in love with a girl who he believes to be a wonderful, flawless, virtuous angel.
In reality, she is a liar, a deceiver, and a cruel manipulator.
In essence, the young man is building his world around an illusion of who she is, not around the reality of what she is.
b. Millions of voters live in an altered state of reality wherein they believe that their political Parties and associated politicians are virtuous, truthful, and concerned about the good of the nation and the taxpayers.
In reality, their elected representatives are power-hungry, tax-and-spend crooks who only care about themselves and their cronies and campaign contributors.
These millions of voters are not living in the real world, but are rather existing in a state of denial and delusion.
c. Many men and women believe that they themselves are attractive, charming, witty, and interesting.
In reality, they are boorish, arrogant, boring, and spectacularly-unfunny.
The people around them (friends and family) only contribute to their illusion by never telling them the truth. (Out of a fear of offending, or a fear of causing hurt or pain.)
Does this make sense?
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