If the scientific method has any authority—or as I prefer to think of it, ‘value’—it is because it represents a systematic approach; but this is valuable only because the alternatives can be misleading. When we reason informally—call it intuition, if you like—we use rules of thumb which simplify problems for the sake of efficiency. Many of these shortcuts have been well characterised in a field called ‘heuristics’, and they are efficient ways of knowing in many circumstances.
