williamgunn, 
If a difference between what you see and what's actually there gives you an existential crisis, you're way overdue for one. Enjoy it and learn from it. https://www.theverge.com/2016/9/12/12885574/optical-illusion-12-black-dots
Start by reading Blindsight: https://www.rifters.com/real/Blindsight.htm
#philosophy #science #perception #opticalillusion