[davidgerard]

> IMHO the term "blockchain", in current and common use, actually means Merkle trees applied to time-series information that is shared between multiple computers over the internet, hence 'distributed database'.

As I note elsewhere in this thread, you literally get that with Git, which was released in 2005 and based on previous work in DVCSes back to the late 1990s. And Merkle trees were invented in 1979.

The new thing in blockchains is the consensus mechanism. The best-known example uses as much electricity as Ireland.

One could call Git a "blockchain", but it'd pretty clearly be trying to synthesise a history for a neologism ...

I suspect "blockchain" products that survive will be tamper-evident transaction ledgers, and I already had one dev admit to me that his company's "distributed ledger technology" product was basically a simplified Git ...

[contingencies]

Good and valid point. To explore further, git has no need to march forward time for a given node, however, and presupposes human intelligence behind all decisions. By contrast, to function at all Bitcoin absolutely requires new blocks to be agreed upon automatically. I feel this is a key distinction. Also, tamper-resistance is not black and white, and is effectively an emergent property with scaling.