Delimiting the human: João de Loureiro, Alexandre Rodrigues Ferreira and the debate on the boundaries between humans and other animals in the second half of the 18th century

Abstract

The article aims to analyze the participation of João de Loureiro and Alexandre Rodrigues Ferreira, both Lusophone naturalists from the second half of the 18th century, in the debate that sought to define the human being and establish its differences from other animals (“natural history of man”). Throughout the 17th and 18th centuries, some authors argued that humans were radically different from the so-called “orang-outang”, a term used by Europeans to describe the great apes they knew at the time (chimpanzees and orangutans). Others contested the existence of such rigid boundaries between them. In the 10th edition of Systema Naturae (1758), Linnaeus introduced Homo troglodytes as an intermediate human species between Homo sapiens and the genus Simia. Buffon, on the other hand, argued for a significant distinction between humans and any other animal. For him, Linnaeus’ Troglodytes also included monkeys. The intention is to demonstrate how Loureiro and Ferreira adopted Buffon's conceptions to criticize elements of Linnaeus's understanding of man: Loureiro sought to refute the idea of different species of men, while Ferreira opposed the idea of the existence of the tailed men – the Homo caudatus. Both criticized as fanciful the narratives claiming the existence of offspring resulting from the crossing of humans and apes. Furthermore, the article highlights the central role of visual representations in the discussions on the subject.