Perhaps nothing is more human than to assume that things easily seen are more real and important than those largely hidden from view. Take icebergs, for example. Typically, we focus on the highly visible tips of icebergs above the water’s surface rather than the much larger masses of ice hidden from us under the cold, dark water. We fail to appreciate how much the tip depends on all of that mass below it in order to float and how much additional mass is hidden from our view....