The great question
How Do You Know?
Enter any belief — scientific, personal, political, spiritual. You will not be told it is true or false. You will be walked through what it would take to find out.
Instead of true / false
The confidence spectrum
1%Almost Certainly False
5%Very Unlikely
20%Unlikely
50%Uncertain
65%Plausible
80%Likely
90%Very Likely
99%Extremely Well Supported
Calibration is the skill of being right about how right you are. Someone who says “90% sure” should be wrong roughly one time in ten. Being wrong less often than that means you are underconfident; more often means the number is decoration.