Were you holding one while he was driving by? lol...

I agree that we can learn to not make assumptions, we have no power over the assumptions that others make. I find it helpful to make very quirky assumptions to help put things into perspective: maybe he ate some bad shrimp and had severe indigestion, and his wife was lecturing him about his driving because he couldn't concentrate on the road. He drove by you and got a hate on because you're out there walking doing something productive and he was he was stuck in the car with his crotchety wife on his way to see his accountant and had to get to a washroom asap.