Hiring is never easy, but hiring for some roles is more straightforward than others. You can test for hard skills, ask references about character, and observe behavior or dig into past achievements to assess leadership. But what if your company is aiming higher? What if you want to change the world (and not just a little)? 

In that case you have to hire dreamers who can not only imagine transformational change but also execute it. How do you find those folks? That is never going to be a cakewalk, but according to Virgin founder Richard Branson there are two qualities you definitely want to look for. 

On his blog recently Sir Richard reflected on a talk at a Virgin Unite gathering by Astro Teller, boss of X, Google parent company Alphabet's "moonshot factory," which is charged with coming up with innovations to create 10X improvements in the world. To be up to that kind of "radical innovation," X employees obviously need to be incredibly smart, but Teller stressed two other qualities he always looks for in employees. They are qualities Branson (and many other super successful people) also insist on when looking for true innovators.  

Audacity 

This first half of Branson and Teller's equation for the ideal innovative hire isn't a huge shock. Clearly, if you're going to improve the world by a factor of ten, you're going to need the audacity to dream big--really big. If a candidate can't talk excitedly and optimistically about things most people think are impossible, they're not going to work excitedly and diligently on them either. Cynicism (or even an excessively restraining definition of realism) is clearly incompatible with radical innovation. 

Humility 

The second half of the equation may come as more of a surprise to many. "For Astro, he's looking for audacity and humility--the audacity to try new things and the humility to be open to the reality that your idea may not work," writes Branson. 

Too much clear-eyed realism can prevent you from getting started on audacious projects, but not enough can prevent you from learning quickly enough from missteps to actually make some of them successful. Audacity without intellectual humility won't get you far. It's a balance Branson insists he's long tried to strike in his own life. 

"I've long publicized my failures and believe that we must feel comfortable in failing. I echo Astro in his belief that most big ideas won't take off--and that we need to be okay with that. We must get smart about proving why things don't work and then move on," he says. 

Teller and Branson aren't the only big names stressing that radical innovation demands not just audacity to set crazy goals but also the humility to see clearly how you're progressing and switch course as necessary to reach them. Jeff Bezos too has stressed the importance of humility, stating he prefers to hire those that can talk freely and intelligently about their mistakes and failures. He understands that the faster you can admit you're wrong, the faster you will learn

Many VCs and entrepreneurs capture this ability to balance commitment and curiosity with the phrase, "strong opinions weakly held." Like Teller, Bezos, and Branson, they see this combination of character traits as a sturdy foundation for radical innovation. (Though some caution that being too loud or certain about those strong opinions can make you into an annoying blowhard and kill productive disagreement). 

So if your company is aiming to change the world in some big way, keep this formula in mind when you hire. Grand ambitions and outsize optimism are great, but to translate dreams into accomplishments, they need to be paired with intellectual humility and the ability to change your opinions in the light of new evidence.