Your credences are Epistemically Rational if and only if:
- They fit with your evidence
- They cohere with eachother
- They update with new evidence
Example
- Suppose you have credence of 0.9 that it will rain this afternoon
- You evidence must favour that it will rain. perhaps you saw dark clouds and saw the weather forecast
- Your credence that it wont rain/will be sunny must be at most 0.1 otherwise, your credences wont add up to 1 and will be incoherent
- If you see that the clouds disappear and it didn’t rain, then your credence will update