> open sourcing both blockchains and the smart contracts that run upon them I agree that the public, replicable nature of the system is attractive, and there's

> open sourcing both blockchains and the smart contracts that run upon them I agree that the public, replicable nature of the system is attractive, and there's some benefit in reusing known technology. But there still needs to be a central authority to "bless" certain actors in the system, else anyone could sign off on anything. A good approach might be for a government health authority to issue "coins" to the various trusted entities in a product's chain of supply, and these then used as proof of stake for transactions in a private blockchain run for that purpose by everyone involved. That would keep bad actors out and would be very hard to hack, while remaining quite public for any interested parties. Now that's a cool idea, however very labour intensive to discover the provenance of any one item; certainly consumers in supermarkets would rely on some kind of query service - and there's your single point of failure again. Still, it's a cool idea. None of this however would have stopped the tampering that launched this whole kerfuffle. Blockchains are excellent at ensuring the perfect reliability of digital data, such as numbers of bitcoins or digital kittens held by whoever owns abc123. They have no such effectiveness on physical products. I mean look at this: > "You cannot open the can of baby food without breaking the label," he says. The melamine was put in before the can was even filled!