10 In 1629 he asks Mersenne to take care of himself " till I find out if there is any means of getting a medical theory based on infallible demonstrations, which is what I am now inquiring."
Fermat, Roberval and Desargues took exception in their various ways to the methods employed in the geometry, and to the demonstrations of the laws of refraction given in the Dioptrics and Meteors.
He was educated there and at Madrid University, where his Radicalism soon got him into trouble, and he narrowly escaped being expelled for his share in student riots and other demonstrations against the governments of Queen Isabella.
In October 1900 Dr Manuel Campos Salles, president of Brazil, paid a visit to Buenos Aires, and was received with great demonstrations of friendliness.
Many of the propositions contained in his dissertation are general; but the demonstrations are not supplied for the case of seven squares.