To: Simone Bronzini <simone.bronzini@chainside.net>,
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>,
	ZmnSCPxj <ZmnSCPxj@protonmail.com>
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From: Dan Libby <dan@osc.co.cr>
Message-ID: <97b3b1a4-f588-65c7-d5cf-e8110ec3e4b5@osc.co.cr>
Date: Fri, 15 Sep 2017 14:48:57 -0700
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Subject: Re: [bitcoin-dev] hypothetical: Could soft-forks be prevented?
Precedence: list

On 09/15/2017 01:40 PM, Simone Bronzini wrote:
> Since a soft-fork is a restriction of the consensus rules, I think the
> only way to have an un-soft-forkable cryptocurrency is creating a
> cryptocurrency where no transaction is valid.
> 
> Imagine I build a very minimal cryptocurrency where in the transaction
> output you only indicate the public key to send your coins to and the
> amount. One can still soft-fork it by deciding that, from now on, only
> even amounts are valid or only public keys that are a multiple of 10 are
> valid.

sure, but in this scenario how would one meaningfully "upgrade" the
functionality, eg add a new opcode?  We couldn't, right?  so....
success!   Preventing new functionality is the primary goal of this
thought experiment.  I believe that common sense and market incentives
would prevent arbitrary tightening of the rules for no good reason...