I'm skeptical about these - as often it's missing the point. Two main challenges: - one world view of categorization does not meet all needs and is fragile ov

I'm skeptical about these - as often it's missing the point. Two main challenges: - one world view of categorization does not meet all needs and is fragile over time - the challenge is still shared understanding between humans, not between computers. Let me explain the second: You have a large set of computer readable definitions - painstakingly built. You have some new data that needs mapping into the ontology. Typically a person has to do that. To map they need to understand the ontology in the same way as every other person doing mappings. The larger, more complex/'definitive' the ontology the harder this is. Finally, science moves on and your ontology/and or understanding is out of date. That's not to say shared definitions are not incredibly useful - just that writing them down in a computer friendly way doesn't guarantee that the definitions are actually shared between people.