"It is possible to provide security against other ills, but as far as death is concerned, we men live in a city without walls"

In this quote, Epicurus is highlighting the inevitability of death and the futility of trying to protect ourselves from it. He suggests that while we may have the ability to protect against other bad luck in life, such as illness or hardship, death is something that can not be prevented. He compares our existence to residing in a city without walls, indicating that we are continuously susceptible and exposed to the risk of death. This idea acts as a pointer to concentrate on living a satisfying life instead of trying to extend it, as death is an inevitable part of the human experience.