 So reflexivity. Reflexes. Ha ha. I'm that fast. You didn't even see the blip it come through the room. All right. So reflexivity. I don't know why that all came out that way, but it did. So it's a stimulus-stimulus relation where a equals a, where if I present the stimulus to you, you will also choose that same stimulus. Kind of weird, right? So you see selection comparison stimulus is the same as a stimulus. Blah blah blah blah blah blah. A equals a. It's really that simple. I mean, this is one of those things that's so simple by showing you a picture of a rabbit and you'll pick a stimulus that is a rabbit and you'll get it. This might not be super useful and well, I guess it is. I'm not going to go there because I was going to offend a whole bunch of people and I've done enough of that today already. So stimulus-stimulus pairings. We just want, not pairings, but stimulus-stimulus training, reflexivity, first step of stimulus equivalence.