Victor Vasarely made this painting, Les Années Cinquante #1, with some kind of printmaking process, or maybe it’s acrylic. Everything is so smooth and flat, like he’s trying to trick our eyes into thinking it’s all happening on one plane. But the shapes and colours are doing something else. They’re kind of fighting for space, pushing and pulling each other in different directions. Look at that light blue shape in the middle – it’s like a shard of light cutting through the red. And the way the blue frame wraps around the other shapes, it’s like the whole thing is about to burst out of its box. It's really controlled, but it gives the impression of constant movement and change. I think of Bridget Riley when I look at this, another artist who liked to play with perception and space. It's like they're both asking: how can we make our eyes dance? How can we make a painting that never stands still?