We all like to think we can spot a good person right away. Sometimes it feels obvious, until it isn’t. Charm can be practiced. Manners can be selective. And first impressions can be misleading, especially when someone wants something from you.
So how do you actually tell whether someone is genuinely good… or just good at appearing that way?
According to a modern philosophy expert, the answer lies in a moral rule that’s more than 300 years old, and arguably more relevant today than ever.
A Question We All Care About
Whether you’re starting a relationship, building a friendship, or entering a business partnership, understanding someone’s moral character matters. You don’t just want to know how they treat you, you want to know who they are when there’s nothing to gain.
That’s where philosopher and popular TikTok creator Juan de Medeiros comes in.
In a widely shared video, de Medeiros offered a surprisingly simple test for judging character, one that traces back to the German writer and thinker Johann Wolfgang von Goethe.
@julianphilosophy Good vs. bad #good #bad #wisdom ♬ original sound – Julian de Medeiros
The Rule That Says Everything
De Medeiros points to a quote commonly attributed to Goethe:
“Never trust someone who is unkind to those who can do nothing for him.”
According to de Medeiros, this single sentence cuts straight to the core of moral character.
“Here’s a pretty good indicator that somebody is a bad person, and vice versa,” he explains. “A bad person is unfriendly to strangers, to the elderly, to children, to service staff, to anybody they’re not trying to impress.”
In other words: watch how someone treats people who offer them no advantage.
Why This Rule Works So Well
It’s easy to be kind when there’s a reward, approval, attraction, power, or profit. It’s much harder to be kind when no one is watching and nothing is at stake.
A person who treats everyone with respect, regardless of status, isn’t performing kindness. They’re living it.
“A good person carries grace within them and shares it freely,” de Medeiros says. “It doesn’t matter who you are or what your status is, they see you as their equal.”
This kind of behavior can’t be faked for long. Eventually, how someone treats the “invisible” people reveals who they truly are.
Enter: The Waiter Rule
If Goethe’s quote sounds familiar, that’s because it shows up in modern culture under another name: The Waiter Rule.
The idea is simple. On a date, in a meeting, or at a restaurant, don’t just pay attention to how someone treats you. Watch how they treat the server.
William Swanson, former CEO of Raytheon, put it this way in his book 33 Unwritten Rules of Management:
“A person who is nice to you but rude to the waiter, or to others, is not a nice person.”
Boxing legend Muhammad Ali echoed the same sentiment:
“I don’t trust anyone who’s nice to me but rude to the waiter. Because they’d treat me the same way if I were in that position.”
Different eras. Same wisdom.
It’s Not Just About Manners
Being rude to service staff isn’t just a character flaw, it often reveals insecurity, entitlement, or a need to feel superior. It shows that kindness is conditional.
And as de Medeiros points out, intelligence plays a role too. Being rude to someone handling your food, your drink, or your service isn’t exactly wise.
More importantly, cruelty toward people with less power is one of the clearest signs of poor moral grounding.
What Goodness Looks Like in Practice
A genuinely good person doesn’t perform kindness for credit.
They:
- Treat strangers with respect
- Speak kindly to elders and children
- Show patience to service workers
- Act the same whether or not they’re being watched
They don’t need an audience. They don’t need a reward. Their behavior stays consistent across situations.
“You are what you do,” not what you claim to believe.
But What About Human Flaws?
Of course, no one is perfect.
Even the best people have bad days, sharp moments, and occasional lapses in patience. As the saying goes, we’re all a mix of light and shadow.
The point isn’t to expect perfection, it’s to recognize patterns.
When someone repeatedly shows contempt for people who can’t benefit them, that’s not a bad mood. That’s character.
Why This Rule Matters More Than Ever
In a world driven by image, branding, and social performance, it’s easier than ever to appear virtuous while behaving poorly behind the scenes.
That’s why this 300-year-old rule still cuts through the noise.
If you want to know who someone really is, don’t watch how they treat their boss.
Watch how they treat the person they think doesn’t matter.
Because how someone treats those who can do nothing for them… tells you everything.
featured image from: Joseph Karl Stieler, Public domain, via Wikimedia Commons