Does the part in boldface mean that the man has the advantage which the weaker species don't have? Oxford dict. states "even" as "equal in number, amount, or value", and "over" as "at a higher level or layer than". Why does "even" pair with "over" here?
As to animals who have really more strength than man has address, he is, in regard to them, what other weaker species are, who find means to subsist notwithstanding; he has even this great advantage over such weaker species, that being equally fleet with them, and finding on every tree an almost inviolable asylum, he is always at liberty to take it or leave it, as he likes best, and of course to fight or to fly, whichever is most agreeable to him.
-- from Rousseau's “Discourse on Inequality”