"Certainty about the future is a sign of mental illness." (NOTE: There's a second lesson here about "we shall (not) be vindicated".)
Why? Because only the self-delusional are absolutely certain about anything... including the future. And self-delusion is a mental illness.
Therefore, thinking only positive thoughts about yourself (well beyond what's needed for self-esteem) and your future is also self-delusion.
But wait, you say, are you saying that I can't give myself a compliment? A thumbs up to myself in the mirror?
No, I didn't say that. Going OVERBOARD with such compliments to the point of ignoring reality is dangerous, and so are anyone trying to dissuade you from reality.
But to explain that, we need to explain how the brain works when it comes to social interactions.
One of the models that tries to explain the brain in terms of human social interaction is called SCARF model:
Status -- relative important to others
Certainty -- being able to predict the future
Autonomy -- sense of control over events
Relatedness -- sense of safety with friends instead of foe
Fairness -- sense of fair exchange between people
One thing your brain craves is "certainty". Your brain simulates possibilities in your dreams based on available data. You feel satisfied when you found out more information, which is why a simple Wikipedia search often turned into hours of related links. Same with Youtube, Google, and such link-heavy sources. Some people like cleaning and organizing. Same idea: they want certainty. Everybody does.
The problem is often, you do NOT have the proper amount of information to achieve certainty, so you end up relying on other things, such as other 4 factors mentioned, like your trust in the friend who recruited you, who trusted someone else, and so on.
The need for certainty is so high that there is a huge market that thrive by selling the FEELING of certainty. The magic formula to investing in the stock market... (bazillions of them, everything from candle chart patterns to "Magic Formula" little book) The tarot card telling your future... The 1-900-PSYCHIC hotline... In fact, many consultants teach company executives how to achieve such certainty through "simulations", "pre-mortems", and so on, Even the entire self-help industry (books, seminars, etc.) is basically selling advice on how to get that feeling of certainty.
Scammers are out there to prey upon your inner desire for certainty, by lying, presenting crooked data, withholding "negative" data, and exploiting your cognitive biases in every way possible to induce you to join their scheme (and put in money) without further due diligence.
One way they encourage you to jump without looking is through enforcing "positivity" (and/or outlawing "negativity") Many view any question or doubt ("Are you sure this is legal?") as "negativity" to be avoided.
Avoiding negativity is just like burying head in sand and see no danger.
|Bury head in sand|
(courtesy of Photovalet.com)
Yet you can sort of understand the need for certainty... But they are obviously going about it wrong. SOME sort of uncertainty is always around us in life. AVOIDING doubt (negativity) to the point of ignoring REALITY is DANGEROUS and often, RECKLESS.
SOME negativity, such as negativity people who gives you negative feedback no matter what, are obviously to be avoided. But ignoring ALL negativity is just STUPID and same as burying head in sand.
Thus, going back to the original question: there is no absolute certainty in life. If you are going after certainty so much you are AVOIDING reality (negativity) you are exhibiting signs of self-delusion, which is a sign of mental illness.
People TEACHING others to "avoid negativity" thus is teaching people to adopt symptoms of mental illness, in the name of "self-help".