Schroedinger's Cats (not really)

I have three cats at home with three distinct personalities. Each morning I open my front door and greet these three cats. The first cat sees me and rushes forward to rub himself affectionately between my legs. The second cat scurries under the porch in fright. The third cat begins meowing insistently at me to feed him and let him into the warm house.

 

I am only myself; one entity. I have not behaved any differently toward one cat more than another. Yet each cat behaves differently toward...