Why Thomas Edison served soup at every job interview

(Image: Tassaphon Vongkittipong)

Deciding who to hire is part science, part art – even if you actually are a scientist.

Take Thomas Edison. When he interviewed candidates for research assistant positions, he offered them a bowl of soup. Why? He wanted to see whether they would add salt or pepper to the soup before they tasted it.

Those who did were automatically ruled out. Edison wanted people who didn't make assumptions, since assumptions tend to be innovation killers.

Many people use little tests as part of their evaluation process. For years, I used what I called the "receptionist test." Interviewees give you their best: They're up, engaged, and switched on. But how do they act when they aren't trying to impress you?

What candidates do while they're waiting in your lobby can tell you a lot, so I would always ask the receptionist how she was treated. I found out what they did while they waited in the lobby. I asked if there were any chance encounters with other employees. Occasionally, I picked up a disconnect between the show a candidate put on for me and the way they acted with people they weren't trying to impress.

After all, a nice guy in the lobby may not be a nice guy on the job, but a jerk in the lobby will always be a jerk on the job.

Or you could use your own version of the Chad Knaus "car test." Knaus is a six-time NASCAR Sprint Cup champion-winning crew chief for a team owned by Hendrick Motorsports (the no. 48 Chevrolet driven by Jimmie Johnson); if you aren't familiar with NASCAR, a crew chief at Hendrick is to auto racing as the head coach of the Patriots is to football.

After interviewing a job candidate, Knaus will sometimes walk with candidates to the parking lot to say goodbye – and to check out their cars. "I don't care what kind of car they drive," Knaus told me. "Old, new, expensive, inexpensive – none of that matters at all. But I do care about whether they take care of their car. If food wrappers are lying on the seats, if the car isn't clean and well maintained – I figure, if you don't take good care of your stuff, you aren't going to take good care of ours."

Is Chad's car test the only hiring criterion that matters? Of course not – but it is another tool to evaluate whether a candidate is a good fit for the team and the overall culture of the Hendrick organization.

Think about what matters most in your organization, and devise your own way to test for cultural fit. Maybe you'll use a version of the server test. (You know how you go out to eat with someone and they're nice to you, yet dismissive of the server? That's the server test.) Maybe you'll do what a friend of mine does, and see if the candidate pitches in to you help stack a few boxes at the end of an assembly line.

Whatever you do, the goal is to learn more about the candidate, so you can make a better hiring decision. Think of it as another way for potential hires to show they are a great fit for the position, and your business.

While it's only one data point in a larger set of hiring criteria, that's okay. You'll be able to make a better hiring decision – and isn't that the whole idea?

Jeff Haden is an Inc. Magazine contributing editor and author of The Motivation Myth: How High Achievers Really Set Themselves Up to Win.

This article was fact-checked and updated in February 2024, and originally appeared in a slightly different form on Inc.com.
 

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