Everyone loves a good optical illusion. Most people first come across them as kids, and are instantly transfixed. And most of us never quite outgrow them. Even cats seem to enjoy the occasional optical illusion! The good news, then, for humans and nonhumans alike, is that our illusions seem to be getting better over time. In the age of social media, lots of people are making and sharing them, and the best ones are quickly going viral and setting the new standard. In effect, our illusions are evolving culturally to be more and more powerful.