Позитивное мышление

Positive thinking has been in fashion for around 30 years. Hundreds of books about how to develop it and become happy and successful have been published and sold in tens of millions of copies. But does it really work? Is it really true that thinking of bad or negative things, like possible problems, misfortunes and ultimately death, inevitably makes you unhappy and depressed? Is there no bias of collecting only facts that prove an idea and ignoring facts that disprove it? Is the whole enthusiasm about positive thinking not just a marketing trick for selling those millions of books? 

The ancients wrote: "Memento mori" (Latin: "Remember that you have to die"), and not all of them were utter pessimists suffering from chronic depression. "Remembering that I’ll be dead soon is the most important tool I’ve ever encountered to help me make the big choices in life." – This was said by a person, whom you would hardly suspect in any hint of pessimism, by Steve Jobs, in his speech at Stanford University in 2005. Did such thoughts prevent him from being successful and happy in his life? It does not seem to be the case. 

Many successful companies, while developing their business strategies, carry out brainstorms on the topic: "What may go wrong with our project? What if it has failed? And what shall we do if this has happened?" This managerial strategy is called "Pre-mortem", in a similarity to the medical post mortem examinations, or autopsy. And if something goes wrong, it does not come to them like a bolt from the blue; they are already prepared and know what to do.