On the contrary. After the many recent quantum physics findings, many of those scientists came forward to explain that our perception of reality is false in many aspects. You might have heard about "the law of attraction". Well, on a quantum level perspective, everything is formed out of energy. Your energy will attract similar energies, so that you will resonate with them. It's a bit complicated to explain without using more complex terms, but the main idea is that every single thought you have (consciously or subconsciously) is actively changing your reality one way or another. This is true whether we believe it or not. Many people claim it's false after "trying" to use it because they are actually just trying to fool themselves that they've changed, when their subconscious mind actually keeps the same old beliefs/patterns/thoughts/etc. Therefore, not only should everyone start thinking positive, they should also actually mean it, because old thought patterns and belief systems aren't easily shaken - it requires time and a strong motivation/desire to change one's life for the better. There are many online courses explaining all about this in-depth (especially on Udemy) - and the authors are well known physicists/psychologists/etc.