It’s like a little window that opens on the animal’s mind. When a ray of light catches the cornea, it reflects in a way that’s almost instinctive, not something a flash can force. That glint shows the exact angle the animal’s looking, the way its pupils dilate, even subtle changes in breathing. Watching those tiny shifts over time tells you whether it’s calm, alert, wary, or engaged. I spend a lot of time just sitting and watching, letting the animal find its own rhythm, and that unforced light is what often reveals what the animal wants to say.