So if I understand correctly Taler avoids double spending by having a trusted central authority? Foss version of Visa/Mastercard basically?
Yes, but it's better. On one hand it's centralized and vendors are regulated, BUT it implements anonymous payment for buyers using a type of blind signature in cryptography (originally envisioned by David Chaum's digital cash), it allows you to pay for things without being tracked and analyzed. In my opinion it's the best compromise between PayPal and cryptocurrencies, I hope one day I can buy things via GNU/Taler.
https://taler.net/en/principles.html
As a payment system must comply with local laws in order to operate legally, GNU Taler must be designed to comply with these requirements. GNU Taler must provide an audit trail for investigators operating under the law. Furthermore, we consider levying of taxes as beneficial to society, and fair taxation requires income transparency. Thus, GNU Taler must enable authorities to track income
Which makes a lot of sense.
Privacy of buyers is protected from the merchant, that doesn't imply that the payment is untraceable (or that complete secrecy is necessary).
If - on the other hand - the government would also like to mass surveil all its citizens, then that is a use case that Taler explicitly and intentionally does not support.
With anonymity for consumer how would transactions like exchanges and returns work?
But not of fighting money laundering. If all income is anonymous, it'd be relatively easy to set up a fake digital-only product and buy yourself lots of it.
It could eventually ease money laundering between countries where laws are different. For example, sell drugs from Netherland, receive Taller coins, buy virtual things from your company in France to move it there. But in fact you can already do that, buy a coffee shop in Amsterdam, and transfer your income after taxes to your bank account in France. Great your are a drug baron living from France now.
What it will prevent is for a country to block their citizen from buying something illegal from another where it is legal, as it is done with card payment and drugs bought online.
Realtime mass surveillance of every party who receives money is isomorphic to realtime mass surveillance of everyone.
Every person who sends funds received them previously and is sending them to someone who is receiving them.
Taler's surveilling is continuous, unaccountable, and operates without any due process what so ever: No court is required to authorize surveilling your records, nor can you even detect it to fight the intrusion.
The claim that the mass surveillance is required to enable taxation is outright untrue and inconsistent with longstanding practice. Taxation, including sales taxes, existed for a long time before low privacy electronic payment networks existed.
I don't believe it is.
For instance, imagine a closed system of three people: Alice, Bob, and Carol. Initially we start off with seeding both Alice and Bob $100 via Taler. We can see that because it is public. Then, we see that Carol receives $5. That is also public. Who gave Carol the $5?
If surveillance of money received is isometric to full surveillance, you should be able to answer this question, but clearly there is insufficient information, so clearly they are not isometric. There may be special cases where sufficiently large transactions can only have come from a small pool of wealthy transactors, but I bet this would be essentially meaningless in practice, and is absolutely not the same as equating the system to full surveillance of every participant.
It doesn't have anything to do with crypto currencies like Bitcoin.
It does make me feel good to see a GNU project like this out there - at the core of the free world IMO, the bits of glue which get our society running, it should really be all open-source and open licenses.
If they're converting to physical goods, they also have to be sending them somewhere - which is much harder to anonymize.
My understanding is that exchanges would do their due diligence before exchanging your fiat for tokens, and separately shops may do due diligance if necessary before accepting your tokens; the exchange does not know that you performed a transaction at this shop, and the shop does not know with whom you exchange[0], but both those relationships have separately done due diligence.
In particular I don't believe there could be a such thing as a "darknet shop" or "darknet exchange" using Taler. If any one entity is not following regulations, it should be possible to track them down and subject them to the law. If a merchant isn't following regulations, then they can't redeem their tokens to fiat at the exchange. If the exchange isn't following regulations, then the auditor/government shuts them down.
[0] not sure about this one
Plus shops will usually have more information: email/address etc.
Current payment providers aren't anonymized. Taler provides anonymity for the spender with blinded signatures.