How much of our lives depend upon illusions? And who is perpetuating those illusions: You alone, someone else to keep you happy, an entire group to which you belong?
How much of our lives are meaningful because of certain fictions? Fictions of: self- importance, friendship, sympathy, compassion?
How can you know if any particular thing about who you are is true, real, not an illusion, not a fiction you've created? I'm not sure you can. And if you can't know that beyond a doubt for yourself, how can you hope to know anything true about anyone else?
All I can be pretty certain of is that we were all born and that we'll all die, we all have bodies that involve biological function. Those things don't seem like illusions, at least, not without adding lots of mystical, magical thinking. Everything else you might want to put into the category of "true" and "real" seems ripe for scrutiny.
The illusions keep us getting up each day and continuing on. It's in creating fictions of who we are and what we're about, that we find meaning. Some days I find this perpetual task invigorating and full of beauty. Today I find it isolating and exhausting. I'm sure Sisyphus had his off days too.