A quick explanation of two types of certainty that people tend to confuse. The first is the one we typically mean in natural language. It's called psychological certainty. It's a feeling of certainty; A confidence in something. This is the one we're talking about when we say things like "Are you 100% sure?". It is possible that someone is 100% psychologically certain that something is true and that the something is actually false. Just think of religious people. Psychological certainty comes in degrees.
Two kinds of certainty
Two kinds of certainty
Two kinds of certainty
A quick explanation of two types of certainty that people tend to confuse. The first is the one we typically mean in natural language. It's called psychological certainty. It's a feeling of certainty; A confidence in something. This is the one we're talking about when we say things like "Are you 100% sure?". It is possible that someone is 100% psychologically certain that something is true and that the something is actually false. Just think of religious people. Psychological certainty comes in degrees.