If I'm going to believe anything, I'd need a longitudinal study of about 5 years.
I find 5 years to be a good hallmark to see whether something had an actual strong impact in my own life (e.g. regarding reading self-help books such as Search Inside Yourself [1] or Steve Pavlina's blog post on how to rock at university [2] -- sorry for being slightly off-topic but these two things changed my life).
I find 5 years to be a good hallmark to see whether something had an actual strong impact in my own life (e.g. regarding reading self-help books such as Search Inside Yourself [1] or Steve Pavlina's blog post on how to rock at university [2] -- sorry for being slightly off-topic but these two things changed my life).
[1] https://www.amazon.com/Search-Inside-Yourself-Unexpected-Ach...
[2] https://www.stevepavlina.com/blog/2006/05/10-tips-for-colleg...
Highly recommended.
https://www.amazon.com/Search-Inside-Yourself-Unexpected-Ach...
p.s. book is worth read IMO.