I spend a lot of time thinking about how people actually make hard calls — at work, in relationships, in business — and I've noticed most "ethics" advice is either too abstract (philosophy 101) or too vague ("just do what feels right").

Here's the single most useful question I've found, borrowed and adapted from Kant: "Would I be okay if everyone in my position did exactly what I'm about to do?"

A few examples of why this works better than gut feeling alone:

• Cutting a corner on a client deliverable "just this once" — feels harmless in isolation. But if every provider cut that same corner "just this once," the whole industry's trust collapses. The rule reveals the real cost your gut instinct hides from you.

• A white lie to avoid an awkward conversation — feels kind in the moment. But if lying to avoid discomfort became the universal norm, no one could trust anyone's word. That's the actual price of the shortcut.

• Taking credit for a teammate's idea — feels like a small career boost. Universalize it: a workplace where everyone quietly stole credit would be one nobody wants to contribute good ideas to.

The reason this question works so well is that it forces you to separate "is this convenient for me right now" from "is this actually defensible as a general rule." Most bad decisions don't survive that test — and most good ones pass it instantly, which is often why they feel obviously right without much deliberation.

It's not the only tool worth having (outcomes matter too — sometimes the "rule" has real exceptions), but as a first-pass filter before you act, it catches more self-serving rationalizations than almost anything else I've used.

Curious if others have a go-to gut check like this for hard calls — work, relationships, or otherwise.