One of them, which self-made millionaire T. Harv Eker identifies in his bestseller "Secrets of the Millionaire Mind," is as simple as what they choose to say.
Rich people never say "either/or" - rather, they say and think, "both."
"Poor and most middle-class people come from scarcity. They live by mottoes such as 'There's only so much to go around, there's never enough, and you can't have everything," writes Eker. "Rich people understand that with a little creativity you can almost always figure out a way to have the best of both worlds."
If you want to live a prosperous life without limits, you have to be willing to think big and abandon the either/or mindset, Eker says.
"Nowhere is 'both' thinking more important than when it comes to money," he writes. "Poor and many middle-class people believe that they have to choose between money and the other aspects of life. Consequently they've rationalized a position that money is not as important as other things."
However, money is important, he emphasizes: "It enables you to 'slide' through life instead of having to 'scrape' by. Money brings freedom ... Money allows you not to have to spend your energy worrying about not having money."
One common misconception that leads average people to say "either/or" is the idea that money and happiness are mutually exclusive - that you have to choose between being rich or being happy. This mindset is limiting, or as Eker calls it: "poor programming."
"From now on, when confronted with an either/or alternative, the quintessential question to ask yourself is 'How can I have both?'" writes the self-made millionaire. "This question will change your life. It will take you from a model of scarcity and limitation to a universe of possibilities and abundance."