Humans aren't the only sentient creatures on Earth. Animals are also the heroes of their own life stories.

Are animals "simple life forms," as a still-dominant tradition of thought proclaims? The distinction between life and mere existence causes animals to be lumped with plants into a homogenous mass – the great "oneness" of Nature – thus reserving the tragedy of individual existence for humans alone. Are we the only creatures entitled to sentience? To live and die conscious beings, experiencing fear and joy? After a critical survey of philosophies that have focused on animals, Florence Burgat ponders the conditions under which a life might be qualified as merely an existence.