They say that you are what you eat. But the truth is that you are who you spend time with. The people we interact with most have the greatest impact on our conversations and the ideas we’re exposed to. The perspectives they espouse tend to influence our own.

Consider that it’s difficult to maintain a positive outlook if you’re surrounded by apathetic people who constantly criticize, belittle, and see the worst in people. In time you’ll likely find yourself agreeing with them, on small points at first, but with increasing frequency as their mentality affects yours.

For those that shoulder considerable responsibility, this tendency can have dire consequences. Associate with unmotivated people, and watch your ambition shrivel. Spend time with defeatists, and your ability to see solutions where others only see problems might dwindle.

But this also presents an exciting opportunity. You can mold your thought processes and focus them on patterns that support your ambitions by seeking out and spending time with people that have already achieved greatness.