Maybe to understand function you need to understand malfunction

Imagine you press the following keys on an old-style calculator (the kind which only displays one input or output at a time on the display): 2 + 2 = You are using your calculator to compute the output of some function. Now imagine your calculator has a bug where sometimes, when you press the "+" button it reads that as a press of the "x" button instead. Your calculator is clearly malfunctioning,…