You exchange fingerprints in-person so you can later attest that the signature corresponds with the person you met IRL.

hueso

signed by your private key...

*damn, then I'm not meeting @ek, problem solved from the root cause!*

Why would I send you my private key, it's private 👀

_And even if, what if someone stole my private key? 👀👀👀_ 

I would then ask @ek to send me a mail with his private [key](https://keybase.io/ekzyis) 😂 problem solved!

Natalia

This is what crypto fingerprints are for.