Seed states that in the Portuguese way of thinking, their invention of the technology that enabled overseas expansion gave them a claim to whatever lands they discovered, whether or not any conquest or territorial possession occurred. According to Seed the technology that allowed for overseas expansion was the ability to fix a latitudinal position using astronomical descriptions. This was thanks to a strong tradition of Islamic and Hebrew mathematics and astronomy in the Iberian Peninsula in particular the Hebrews who solved the practical problems of navigation.
Having this technology to discover and fix the latitudinal position of unknown lands gave Portuguese merchants the right to establish trading monopolies with the natives. Because Portugal’s claim in the new world was based upon new knowledge, new knowledge is exactly what they sought so they left very little physical marks as their sign of discovery unlike the other Europeans and instead continued mapping the world. This can help to explain why Seed does little at all to mention the Portuguese relationship with the indigenous people of