That author uses it to mean “model”, as he calls a variety of programming models “spherical cows”. Well, for sure, a core tenet of computer science is that all

That author uses it to mean “model”, as he calls a variety of programming models “spherical cows”. Well, for sure, a core tenet of computer science is that all models of computing are equally powerful in what inputs they can map to what outputs, if you set aside any other details