Alexandre de Gusmão
![Non contemporary portrait by Oswaldo Teixeira](https://upload.wikimedia.org/wikipedia/commons/e/e7/Retrato_de_Alexandre_de_Gusm%C3%A3o.png)
Born in the city of Santos, he may be considered one of the precursors of the application of Enlightenment principles to international relations, adopting the principle of ''uti possidetis'', according to which each state has the right to the land that it actually occupies, as well as the idea of "natural boundaries", which suggests the use of prominent geographical accidents – such as rivers and mountain ranges – to set the limits between states.
He graduated in Law and was the representative of Portugal to various states, among which Rome, where he came to be invited to join Pope Innocent XIII's court. He was also a brother of Bartolomeu de Gusmão, a priest and naturalist recalled for his early work on lighter-than-air airship design (balloons). Provided by Wikipedia