“Beasts, Men, Aliens, Spirits and God: John Locke and the Chain of Life”

In this paper I will analyse Locke’s views on the possibility of extra-terrestrial life. As suggested by the title, An Essay Concerning Human understanding, published in 1689 by the English philosopher John Locke, consists of an investigation into the man’s understanding. However, the inquiry about the limits and extent of human knowledge led to reflection on the order of creatures that surround the universe and are objects of curiosity or scientific research. Thus, the object of natural philosophy is divided between beings material and spiritual beings that inhabit the material world and the intellectual world, respectively. From this division, it is possible to establish a diversified chain of being as follows: 1) At the bottom of the chain were beasts, animals and vegetables or simply sentient beings and material formed by an organized and permanent corpuscular structure. 2) Then participants were men of the material and sensible world, as well as the intellectual and rational world. Even on these two categories, Locke advocates the probable existence of extraterrestrial beings. In other words, Locke advocates the possibility of life on other worlds and not only the existence of simple and merely sentient beings, but also of intelligent life, possibly having higher cognitive ability to that of humans.