We are certain because we treat it as an axiom (loosely speaking) of our epistemology. We’re as certain of it as we would be of a logical truth. In practice we are fallible and can make mistakes about logical truths. But in theory, they are absolutely certain; they have a higher status than mere beliefs about the universe.
Assigning 1.0 probability to any proposition means you can never update away from that probability, no matter what the evidence. That means there’s a part of your map that isn’t causally entangled with the territory. What we’re certain of is that there shouldn’t be such a part.
We are certain because we treat it as an axiom (loosely speaking) of our epistemology. We’re as certain of it as we would be of a logical truth. In practice we are fallible and can make mistakes about logical truths. But in theory, they are absolutely certain; they have a higher status than mere beliefs about the universe.
Assigning 1.0 probability to any proposition means you can never update away from that probability, no matter what the evidence. That means there’s a part of your map that isn’t causally entangled with the territory. What we’re certain of is that there shouldn’t be such a part.