I do not perceive a "high-resolution"-curve (for example, 14 and 15 is hard to distinguish on the curve, but 12 and 18 is easy to distinguish). So, when I think

I do not perceive a "high-resolution"-curve (for example, 14 and 15 is hard to distinguish on the curve, but 12 and 18 is easy to distinguish). So, when I think about a number I approximately know where on the curve to assign it.