Smart contracts can’t even do anything interesting without a trusted source of data input.
...for a certain definition of "doing anything interesting", just as well as "trusted source"*.
As the locus of economy shifts more and more away from physical widgets and into information, the value of information goes up in relation to physical widgets. This makes Blockchain a practical, if not all-encompassing, tool for verification.
Compare a plain old car - the software onboard is a small fraction of its value - to any half-decent workstation, where the value of software can easily exceed the hardware's value several-fold.
Proving I had certain information at certain time point - e.g., a license for the software, or CAD design or other valuable file I've created - can easily provide a lot of value. And in this case "trusted source of information" is the mere fact of existence of a cryptographically secured license file naming me as the licensee at certain time point. Easily securable with the Blockchain.
Proving I had certain information at certain time point
The blockchain solves the problem of proving ownership of a transferable asset. If you just want to prove that you have certain information at a certain time point there are much simpler solutions: Publicly release the hash of a message (let's say: "I created this using the licence key XXX-XXX-XXX" + signature from your private key) on Twitter/Facebook/Github/Archive.org etc.
Or even better: Sign a contract and send it to your law firm. Once someone breached a licence/contract you need to involve lawyers/regulators anyway.
an interesting way of describing a crypto blockchain like bitcoin or ethereum is that it's a way of incentivizing the storage and preservation of information. In particular, the information of a transaction from one address to another is attached with it a fee for storing it. Your "much simpler solutions" require a trusted third party that has no financial incentive to keep your information around, and depending on the lifetime of your needs may not persist long enough. 10 years ago your solution may have involved myspace or further back geocities or tripod, which are defunct / have refreshed their databases. Spending under 10 cents on a miner fee to store your hash is also a much better solution and cheaper solution than the lawyer escrow. Lawyer escrows and safes are vulnerable to local information loss that bitcoin/ethereum protects against through federated datastores (lots of important papers stored in the world trade center were destroyed on 9/11).
For ~20$ you can publish a hash in a classified ad. That's highly likely to outlast any and possibly every block chain you care to name. Further, because the way hash functions work you can use a single hash to timestamp unlimited amounts of information or individual documents.
This has been true for the last 30+ years yet almost never happens because it's not actually that useful.
Comments
Smart contracts can’t even do anything interesting without a trusted source of data input. ...for a certain definition of "doing anything interesting", just as well as "trusted source"*.
As the locus of economy shifts more and more away from physical widgets and into information, the value of information goes up in relation to physical widgets. This makes Blockchain a practical, if not all-encompassing, tool for verification.
Compare a plain old car - the software onboard is a small fraction of its value - to any half-decent workstation, where the value of software can easily exceed the hardware's value several-fold.
Proving I had certain information at certain time point - e.g., a license for the software, or CAD design or other valuable file I've created - can easily provide a lot of value. And in this case "trusted source of information" is the mere fact of existence of a cryptographically secured license file naming me as the licensee at certain time point. Easily securable with the Blockchain.
The blockchain solves the problem of proving ownership of a transferable asset. If you just want to prove that you have certain information at a certain time point there are much simpler solutions: Publicly release the hash of a message (let's say: "I created this using the licence key XXX-XXX-XXX" + signature from your private key) on Twitter/Facebook/Github/Archive.org etc.
Or even better: Sign a contract and send it to your law firm. Once someone breached a licence/contract you need to involve lawyers/regulators anyway.
an interesting way of describing a crypto blockchain like bitcoin or ethereum is that it's a way of incentivizing the storage and preservation of information. In particular, the information of a transaction from one address to another is attached with it a fee for storing it. Your "much simpler solutions" require a trusted third party that has no financial incentive to keep your information around, and depending on the lifetime of your needs may not persist long enough. 10 years ago your solution may have involved myspace or further back geocities or tripod, which are defunct / have refreshed their databases. Spending under 10 cents on a miner fee to store your hash is also a much better solution and cheaper solution than the lawyer escrow. Lawyer escrows and safes are vulnerable to local information loss that bitcoin/ethereum protects against through federated datastores (lots of important papers stored in the world trade center were destroyed on 9/11).
For ~20$ you can publish a hash in a classified ad. That's highly likely to outlast any and possibly every block chain you care to name. Further, because the way hash functions work you can use a single hash to timestamp unlimited amounts of information or individual documents.
This has been true for the last 30+ years yet almost never happens because it's not actually that useful.