NOTshadows are nice, aren’t they? See what you are able to do with them. You may add, subtract, divide. You may calculate the variety of atoms within the recognized and observable universe, or the instances you needed to ask your daughter to tidy up her room; use them to order a couple of pizza, underestimate the speed of world warming, or exaggerate the dimensions of issues as numerous as planets and escaped fish. For quantitative analysis, the rule of numbers.