It is raining profusely outside. Inside, sheltered, your skin does not feel the wetness of the sky. To see the rain, you can look through the window at the drops pouring from the sky, focusing on their motion, bulbous shape, and intensity. Or, you can concentrate on the window pane, itself home to parasitic rain drops which try desperately not to slide down the pane to their deaths and which, in doing so, obscure the normal transparency of the glass. Although you are looking in a single direction, seemingly at the same point in space, and you are essentially observing the same phenomenon in both viewing cases, you can never see both at once. Your focus must flit back and forth between the two. This constant alteration of focus is similar to the way we approach the house/home dialectic. What is perhaps most interesting, is that without seeing the raindrops falling, it is impossible to empirically explain why the window is wet, and without seeing the wet window, one cannot not understand the viscosity of water, the friction produced by a seemingly smooth glass surface as compared to air.