In the case of unequal catheti also, and indeed generally in the case of every possible geometrical truth, it is quite possible to obtain such a conviction based on perception, because these truths were always discovered by such an empirically known necessity, and their demonstration was only thought out afterwards in addition.
besterik ez bada, horren aurkikuntza horrelako beharrezkotasun begietsi batetik abiatu zelako beti, eta frogapen horren atzetik bakarrik izan baitzen imajinatua: