> On the one hand "Proof of humanity" is an important problem and is surely only going to get more important as time passes
Governments have been doing this for centuries (see passports, identity documents, birth and death certificates). Witnessing attempts by private entities repeated attempts to "solve" this problem and make a profit has shown me the limitations of free markets. Despite the complexity and sophistication of the implementation, it boils down to a record that's looked up by a trusted entity who attests the validity of the subjects identity, or not.
Governments have been doing this for centuries (see passports, identity documents, birth and death certificates). Witnessing attempts by private entities repeated attempts to "solve" this problem and make a profit has shown me the limitations of free markets. Despite the complexity and sophistication of the implementation, it boils down to a record that's looked up by a trusted entity who attests the validity of the subjects identity, or not.