Yes, it can, particularly in the phrase "positive thinking."
There was a famous book, published in 1952, entitled "The Power of Positive Thinking," by Norman Vincent Peale, which advocated optimism.
And, on the other side, in 2009, a writer named Barbara Ehrenreich published a book entitled "Bright-sided: How the Relentless Promotion of Positive Thinking Has Undermined America."