Hilma af Klint made this painting, one of her series titled "The Dove," with oil and tempera in a truly experimental way. There's something so intriguing about the texture and color. The colors feel diluted, a bit chalky. It’s as if she built up the image slowly through layers, with each layer revealing some kind of new element of her process. Look at that central helix, it is so precise, yet organic, acting like a kind of plumb line for all the more amorphous shapes that surround it. In a way, the whole piece reads as a conversation between these two modes, the structural, and the felt. The way Klint allows us to see the brushstrokes, and keeps the surface somewhat open is an invitation, I think, to watch her thinking. Agnes Martin also had this approach to painting as a way of thinking, and both artists were dedicated to exploring different kinds of perception through their work. In the end the real subject is the process of seeing itself.