When overused these positive thinking mantras can become a bit tiresome. But, maybe there is still some relevance to modern macroeconomics. Not least, we have the phrase of ‘talking ourselves into a recession’. The idea that if key people in the economy keep talking about a recession, this can become a self-fulfilling prophecy. With a threat of recession, people spend less, firms invest less and this creates falling aggregate demand.
http://www.economicshelp.org/blog/6670/article/economics-and-positive-thinking/#more-6670
