The Greeks were very interested in measuring things by comparing them to a set unit. They found that there was a relation between pairs of measurements such as the ratio or the quotient. They were also interested in proportion e.g. when two ratios are equal. They were also interested in "beauty". They referred to the most beautiful proportion as golden ratio (from gold) and the number represented by the symbol F is the golden number. It appears in nature and the Greeks were the first to apply...