Hard and Soft Forks - Mike Hearn and then I respond

[psztorc]

https://medium.com/@octskyward/on-consensus-and-forks-c6a050c792e7

I have to say I was very shocked at Hearn's point of view...it seems obviously "the wrong way to look at it". (Maybe it's me).

[psztorc]

Mike responded a few times. He seemed to disagree with ...

Say x is "the probability that a severe bug is discovered in Bitcoin". Would you agree that a soft fork cannot increase x, whereas a hard fork can?

... on the grounds that soft forks can also create bugs. While soft forks may introduce new bugs in their new specialized features, they (by definition) can't burden users with any existential-threat-bugs that weren't already in the cryptosystem. Mike has yet to respond.

[psztorc]

I fleshed out my reasoning, syllogism style:

Clearly you would agree that:

[P1] If someone could have killed the Bitcoin cryptosytem, they would have done it by now (Gavin's SilkRoad point). [P2] No one has killed Bitcoin yet. So, [C1] Bitcoin is currently immune to murder.

You probably also agree with:

[P3] All that is 'done' must either be intentional-doing or unintentional-doing. [P4] " Bug means 'software does not do what it was intended to do' ". So, [C2] one who intentionally reduces the number of things a software 'can do' is unable of increasing the frequency of bugs ("unintended behavior").

But it then follows that:

[P5] Soft forks intentionally reduce the number of things a software 'can do'. + [C2] = [C3] Soft forks are unable to increase the frequency of bugs ("unintended behavior").

And then:

[P6] As "unintended behavior" is "unintended", we don't know what it is, and so "it" might include "death". + [C3] = [C4] Soft forks are unable to increase the likelihood of Bitcoin dying.

Do you agree with [C4]? In the past, I think you have argued that organic user growth under 1MB blocks will kill Bitcoin, but I feel this premise contradicts (and is inferior to) [C1].

Does this demonstrate [C4]? If C4 is true, is "Would you agree that a soft fork cannot increase x, whereas a hard fork can?" true? Does it imply that we should be cautious (+90% developer consensus) when attempting hard forks?