Quote from: monsterer on February 16, 2016, 09:17:56 AM

Another point, I wanted to touch on this idea of 'Turing completeness'. I'm not sure it's entirely helpful to the discussion on Ethereum because, even the computer I am writing this message on cannot be classed as 'turing complete' in the true sense of the definition.

I believe your point is related with script inputs being external to the blockchain? If the inputs to a script must come to that script via a transaction, that internalises the inputs - so I must be missing something?

Quote from: monsterer on February 16, 2016, 09:35:42 AM

Quote from: TPTB_need_war on February 16, 2016, 09:22:52 AM

Also I have pointed out in my video and the follow up posts in this thread about a meta issue that destroys the Nash equilibrirum, that for the case where there are external failures (external to the block chain's perspective of itself) due to external actuation of cross-partition state, the Nash equilibrium fails because the entire coin fails

If all inputs to a script arrive via one transaction, you must be forced to conclude that there is no difference between said scripting blockchain and an asset transfer chain in terms of equilibrium breakdown?

edit: actually, I see what you're saying - if the script author's cause a cross partition dependency, that dependency can affect the resulting ordering on partition merger. The problem is when this dependency is not visible to the system.

You got it with the edit. You must have re-read my prior post and the edits I had done on my prior post.

The issue is the system thinks it has strict partitioning, but the external users can violate that partitioning of state (at least with scripts, not sure yet about only asset transfers). The system thinks that the state of one partition can't impact the state of another partition, but the external users can violate this assumption if there exists the ability to apply external input to the block chain (which obviously must exist otherwise the scripting is mostly useless, i.e. no new accounts, etc).

For asset transfers, I need to think about the harm that can be done and whether the same problem applies. For scripting (with external I/O) it is clearly impossible to assume/enforce strict partitioning of state.

Quote from: monsterer on February 16, 2016, 09:35:42 AM

further edit: however, I still struggle to see why this would result in anything more than the failure of the script in question?

No script fails from the perspective of the block chain. The external users see failure, because only the external users are aware they violated the strict partitioning of state. And thus the spaghetti of external failure becomes as intertwined as inputs and outputs from many partitions cross-pollute cascades and intertangled scripts.

Edit: the block chain thinks it is validating the block chain because it erroneously thinks strict partitioning is enforced. External users see that validation is failing, because they violated the assumption of strict partitioning by cross-polluting the state via the external I/O of the block chain. Thus holistically and systemically there is failure (from the perspective of the external users and thus the coin's market value plummets as users abandon the system due to failures).