Kitap 1
10.39
Again oratory sometimes detects falsehoods closely resembling the truth by the use of geometrical methods. An example of this may be found in connexion with numbers in the so-called pseudographs, a favourite amusement in our boyhood. It is not known to what Quintilian refers. But there are more important points to be considered. Who is there who would not accept the following proposition? When the lines bounding two figures are equal in length, the areas contained within those lines are equal. But this is false, for everything depends on the shape of the figure formed by these lines,
10.40
and historians have been taken to task by geometricians for believing the time taken to circumnavigate an island to be a sufficient indication of its size. For the space enclosed is in proportion to the perfection of the figure.
10.41
Consequently if the bounding line to which we have referred form a circle, the most perfect of all plane figures, it will contain a greater space than if the same length of line took the form of a square, while a square contains a greater space than a triangle having the same total perimeter, and an equilateral triangle than a scalene triangle.
10.42
But there are other points which perhaps present greater difficulty. I will take an example which is easy even for those who have no knowledge of geometry. There is scarcely anyone who does not know that the Roman acre is 240 feet long and 120 feet broad, and its total perimeter and the area enclosed can easily be calculated.
