The cause why you have performed nothing in any of your books (saving that in your _Elenchus_ you have spied a few negligences of mine, which I need not be ashamed of) is this, that you understood not what is _quantity_, _line_, _superficies_, _angle_, and _proportion_; without which you cannot have the science of any one proposition in geometry. From this one and first definition of Euclid, “_a point is that whereof there is no part_,” understood by Sextus Empiricus, as you understand it, that is to say misunderstood, Sextus Empiricus had utterly destroyed most of the rest, and demonstrated, that in geometry there is no science, and by that means you have betrayed the most evident of the sciences to the sceptics. But as I understand it for _that whereof no part is reckoned_, his arguments have no force at all, and geometry is redeemed. If a line have no latitude, how shall a cylinder rolling on a plane, which it toucheth not but in a line, describe a superficies? How can you affirm that any of those things can be without quantity, whereof the one may be greater or less than the other? But in the common contact of divers circles the external circle maketh with the common tangent a less angle of contact than the internal. Why then is it not quantity? An angle is made by the concourse of two lines from several regions, concurring, by their generation, in one and the same point. How then can you say the angle of contact is no angle? One measure cannot be applicable at once to the angle of contact, and angle of conversion. How then can you infer, if they be both angles, that they must be homogeneous? Proportion is the relation of two quantities. How then can a quotient or fraction, which is quantity absolute, be a proportion? But to come at last to your _Epiphonema_ , wherein, though I have perfectly demonstrated all those propositions concerning the proportion of parabolasters to their parallelograms, and you have demonstrated none of them (as you cannot now but plainly see), but committed most gross paralogisms, how could you be so transported with pride, as insolently to compare the setting of them forth as mine, to the act of him that steals a horse, and comes to the gallows for it. You have read, I think, of the gallows set up by Haman. Remember therefore also who was hanged upon it.