What we KNOW ain’t necessarily so.
Look at the two lines above and ignore the chevron – arrow shapes connected to them. Which is longer? Take a moment to be sure. Okay, now measure them. Which is longer? So now you KNOW which is longer, right? Neither. They are the same. This is a famous optical illusion that you have doubtless seen before. So you REALLY know they are the same. But … how do they