Money may be able to buy happiness after all, Bill Gates suggested during his seventh "Ask Me Anything" session on Reddit on Monday.

A user asked, "Do you think being a billionaire has made you a happier person than if you were just a middle class person?" The Microsoft co-founder responded: "Yes. I don't have to think about health costs or college costs. Being free from worry about financial things is a real blessing."

He added, though, that "of course, you don't need a billion to get to that point. We do need to reduce the cost growth in these areas" — health care and education — "so they are accessible to everyone." Both are systems in which he and his wife Melinda have invested billions and which they are are determined to help improve.

Gates, who is worth nearly $100 billion, is not the only high earner with this mentality.

After researching more than 1,200 self-made millionaires, author Steve Siebold found that the wealthy aren't afraid to admit that money can solve most problems.

"The rich see money as a positive tool that has the power to create freedom and opportunity for themselves and their families," Siebold writes in "How Rich People Think." After all, "if you have a problem, and you can make it disappear by writing a check, you don't have a problem."

Accepting that money can create options is a key reason the rich continue to generate more wealth, he says: "While the world class sees money as a critical resource that opens up endless possibilities, the middle class is demonizing it and denying its importance."