I haven't read a lot of theory on the death drive but I like to consider it in the terms that Campbell used to refer to a specific psychic impulse. As the body grows older, the mind seeks to identify itself less and less as an embodied entity. The mind has to deal with the fact that the body is in a state of decay followed by cessation, and this knowing compels us to seek external stuff to identify with. Mementos of our presence, in our absence. So, we become like signs. We enter the realm of the unchanging symbol, etched like stars into the sky. Carried on in the memories of those we knew.
Sometimes our minds can drive our bodies to death, sometimes, even intentionally and immediately. It is telling that we are the only species (I think) capable of such a feat, and we are also the only species (we assume) that makes a distinction between our minds and our bodies.
Is this the sentience we talk about when we consider ourselves in contradistinction to other forms of animal life on earth? This ability to negate our bodily desires and act in accord with other stimuli of a more abstract and less immediate nature. This is what we seem to want to say is different about us than other forms of animal life.
This is really the religious argument for human identity, and I think in many ways it is more compelling than something like:
1. our use of language is unique (more highly developed)
2. our usage of tools and our ability to manipulate the external environment is also unique and more highly developed
Which are scientific-style arguments.
You can't really wrestle with them. Of course our usage of tools is unique because it's more highly developed.
At any rate, this history of Western religion which is Platonically influenced, pits the mind at war with the body in a very conscious way.
At any rate, the evolution of Western Economics involves the coin which is the representation of wealth or property, slowly losing its connection to material wealth and thus mirrors the Death Drive.
It also coincides with a disjunction between the word and concept found in Post-Modern critiques of the Western philosophic tradition.
Think of it in terms of:
Bought the farm
Bit the dust
You have two cliches which are dead metaphors which refer to the same event, but convey the sense of it in distinct ways.
If you are hearing "bit the dust" for the first time you may be thinking hmm, I got some dust in my mouth, I guess I'm on the ground, or in the ground, oh yeah, I'm dead." But we don't have to parse this out anymore. We auto-swap the death for the "bit the dust" and it loses it's tangible connection to the sensibility it had.