I miss this, what is the difference between ecash and centralized sats wallet?
Ecash mints are banks.
No difference. They can lie about timestamp too.
Discussion
“Ecash is the purest/leanest form of money as data. It can probably not get any leaner than just a text string.”
So Ecash sat can be used as a stamp. Centralized wallet sats are just database records and cannot be used as stamps.
I'm not so expert about ecash, so I don't know which data is included in that qr/string. But if there is a tmestamp it can lie or be wong for various reasons. So how it can be a proof? Please explain or fuck of me.
I have to read the fucking manual.
You might have misunderstood. I meant that ecash sat can be used as a postage stamp.
Relays receiving the stamp can verify it is a real sat by redeeming the ecash stamp at the mint for LN sat, and then forward the message. 
Ok took it, So one sat for relay for message. That's becoming expensive. I value privacy and freedom too, but not so rich. A feature like that is for very important messages.
Maybe spending 90 cents a month shouldn't be too expensive?
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