In his essay How to Start a Startup, entrepreneur and Silicon Valley oracle Paul Graham describes an “animal” as someone who takes their work a little too seriously.

They do their job so well that “they pass right through professional and cross over into obsessive.”

Animals may not fit well in large companies, but in startups they’re essential.

In practice, what exactly an animal does depends on their particular role – here are some examples:

The animal test is easy to apply: call to mind someone you know, and imagine the description “so-and-so is animal.”

If you laugh, they’re not.

Retired U.S. Army general Stanley McChrystal, in an interview with author Tim Ferriss, talks about the importance of measuring a candidate’s self-awareness when they’re applying for a job.

McChrystal uses the following two-step technique when he’s interviewing candidates for his leadership consulting firm McChrystal Group:

This puts the candidate in the position of having to articulate how other people perceive them.

That perception may be common knowledge, but the prompt accomplishes 2 things:

As McChrystal puts it, if the person doesn’t have the courage to acknowledge this perception and tell it to someone who’s considering hiring them, then “that’s a window into personality.”

Amazon CEO Jeff Bezos writes in a 1998 Letter to Shareholders that “Setting the bar high in our approach to hiring has been, and will continue to be, the single most important element of Amazon.com’s success.”

In hiring meetings, Bezos encourages colleagues to consider the following 3 questions before making a decision about a candidate:

As Bezos points out, if you think about people you admire, they are probably people you’ve learned something from or who have served as an uplifting example. You should try hard to work only with people you admire: “Life is definitely too short to do otherwise.”

Bezos wants to make sure that the quality of people Amazon hires is always increasing. He asks colleagues to imagine the company 5 years in the future; their reaction at that point should be: The standards are so high now – boy, I’m glad I got in when I did!

Many people have unique interests, perspectives, and skills that enrich the work environment, even though these qualities may not relate directly to a person’s job. Bezos gives the example of an Amazon employee who is a National Spelling Bee champion: “I suspect it doesn’t help her in her everyday work, but it does make working here more fun if you can occasionally snag her in the hall with a quick challenge: ‘onomatopoeia!’”

“We look for three things when we hire people. We look for intelligence, we look for initiative or energy, and we look for integrity. And if they don’t have the latter, the first two will kill you, because if you’re going to get someone without integrity, you want them lazy and dumb.”

- Investor Warren Buffett in a speech to MBA students at the University of Georgia