Quote from: jubalix on June 19, 2016, 10:52:47 AM

Vitalik
https://blog.ethereum.org/2016/06/19/thinking-smart-contract-security/

"However, it does show that there is a fundamental barrier to what can be accomplished, and fairness is not something that can be mathematically proven in a theorem"

well yes it can:

If you hold a system will function in a particular way and it does then that is fair, and you can mathematically prove it
https://www.reddit.com/r/ethereum/comments/4opjov/the_bug_which_the_dao_hacker_exploited_was_not/
TL;DR - Complexity and "Turing completeness" are not the real culprit here...

How many times am I going to have to repeat myself and link to my explanation that the quoted Reddit above is INCORRECT!

https://bitcointalk.org/index.php?topic=1505886.msg15273470#msg15273470 <--- click & read please

Vitalik is correct. The Reddit post is not. Period.

Turning-complete programming on a block chain can't be guaranteed to be secure. There will always be a gap between "intent" and "execution".

The fundamental reason is tied into the Halting problem, in that one can't prove an absolute negative, e.g. prove that no dinosaurs are still alive any where in the universe. It is undecideable.

Fundamentally this is the Second Law of Thermodynamics and the fact that time is irreversible so entropy is unbounded. The only way that wouldn't be the case would be if the speed-of-light was not finite, but then the past and future would collapse into the same infinitesimal point of nothingness and nothing could exist.

Theorem provers such as Coq produce output that is not Turing-complete. Yet that isn't even relevant, because "intent" can't be absolutely quantified in code or specification because interpretation is relative, i.e. the only account of history which is 100% certain doesn't exist (people will disagree on what happened because no one was every where in real-time, i.e. the speed-of-light is finite).

If you can't grasp this, don't fret. It requires a high level of intellect and also understanding of several fields including computer science and physics.

The bottom line is that Turing-complete programming on a block chain is "a can of worms" which is what we all told Ethereum since back in 2013 when Vitalik first proposed it.

Quote from: BitUsher on June 19, 2016, 01:11:16 PM

Another attack occurring?

https://www.reddit.com/r/ethtrader/comments/4ot3vi/warning_another_successful_attack_recursive_split/

Quote from: BitUsher on June 19, 2016, 02:04:36 PM

Published on may 18th

Ethereum Contracts Are Going To Be Candy For Hackers

http://vessenes.com/ethereum-contracts-are-going-to-be-candy-for-hackers/

Quote from: iamnotback on June 19, 2016, 02:29:07 PM

Quote from: toknormal on June 19, 2016, 12:03:27 PM

It isn't "tarnished forever" if the problem is confined to where it originated. That was the whole point of a "Turing Complete" scripting language - to isolate one contract from another and from the underlying platform itself as I've explained here and in previous posts in that thread.

I responded to your linked post as quoted above:

Quote from: iamnotback on June 19, 2016, 02:26:49 PM

Quote from: toknormal on June 19, 2016, 11:26:55 AM

The very architecture of a smart contract blockchain makes the logic of the "Turing Complete" scripting language independent of the logic of the blockchain on which it runs. Kind of like the separation of executive a legislative powers in states. If you decide to p*ss all over that principle just to save yourself embarrassment and investors in a known risky asset from taking a haircut then you just kill it for everybody.

Incorrect! Turing-completeness is unbounded recursion. Thus it makes it impossible to encapsulate scripts from each other and from internal recursion, etc.. It is the opposite of your incorrect assumption!

You should stop spreading lies about computer science that you do not understand.