A big part of social capital is having people who want you to succeed–people who follow you, stick by you, and help you to the heights of greatness. But this isn’t always easy, especially if you’re a pessimist. It’s important to exude optimism. Take a lesson from Bob Iger, Disney’s recently retired CEO who revitalized the company and secured its place as an entertainment powerhouse in the 21st century.

After the 9/11 attacks, there was a global decline in tourism, and, as a result, Disney’s businesses suffered. This time was also a period of conflict for Iger’s predecessor, Michael Eisner, as Disney struggled to handle the downturn.

In his book, Iger recounts how Eisner would succumb to the stress, spiral into paranoia, and project a sense of doom that permeated through the ranks. It was ruinous to company morale. Iger says, “No one could have handled the stress that Michael was under perfectly, but optimism in a leader, especially in challenging times, is so vital. Pessimism leads to paranoia, which leads to defensiveness, which leads to risk aversion.”

Iger makes an argument for Optimism:

“Optimism sets a different machine in motion. Especially in difficult moments, the people you lead need to feel confident in your ability to focus on what matters, and not to operate from a place of defensiveness and self-preservation. This isn’t about saying things are good when they’re not, and it’s not about conveying some innate faith that “things will work out.” It’s about believing you and the people around you can steer toward the best outcome, and not communicating the feeling that all is lost if things don’t break your way. The tone you set as a leader has an enormous effect on the people around you. No one wants to follow a pessimist.”

To succeed, you need people that want to stick by you, follow you, and help you to the heights of greatness. A pessimist won’t get this response.