The message of these myths is that invulnerability is precisely that, a myth. There is always one unforeseen weak point, one flaw. He has felled a dragon but will die from a fallen leaf. The lesson is not only that invulnerability can never be total, but also that any attempt to achieve invulnerability in turn engenders a corresponding vulnerability. It is by grasping Achilles’ body in order to plunge it into the river that Thetis makes it invulnerable and at the same time produces its vulnerable point, which is the spot at which she grasped it. With regard to invulnerability and vulnerability, these two, far from excluding one another, each summon up the other.

Grégoire Chamayou, A Theory of the Drone, loc. 291