(adapted and cross-posted from http://rationallongevity.blogspot.com)

The notion that some creatures on the Earth are here specifically for humans, for our use, and exploitation, is quite distasteful to me (and smacks of a misinformed application of the Anthropic Principle), but it cannot be denied that humans do benefit from the existence of, and the destruction of, certain other organisms. The psychological "toll" of sentience is, perhaps, knowing that by virtue of our own continued existence, we are exerting dominion over the life and death of other organisms with varying degrees of sentience. We kill multitudes of bacteria whenever we clean our bathrooms, we unwittingly (or intentionally) step on ants, we burn fuel, we create waste.

Some take this acknowledgement and use it as a basis for a particular brand of self-loathing that manifests in such doctrines as original sin and deep ecology, as well as everyday, garden-variety statements to the effect of, "Well, we're all part of the intricate web of nature, and we should make no heroic attempts to stave off our own deaths, because obviously if everyone lived forever we would be upsetting the balance of existence."

By this doctrine, death is an equalizer and a judge: either in the sense that it brings a person passage to either paradise or damnation, or in the sense that oblivion is justice served for a few decades of knowingly exerting one's influence on the universe. There are a number of ideological traps that can keep people confined to this mode of thinking, and, more frighteningly, compel such people to assert that their views are more important than the survival of those who disagree.

These doctrines and statements are possibly an expression of deep guilt on the part of sentient beings at realizing they exist, and knowing that in continuing their existence, they must necessarily consume resources, change their surroundings, and destroy other organisms.

If one finds tragedy and horror in the mechanisms of unaltered nature, and yet believes these mechanisms to be part and parcel of a proper and even sacred existence, one must remember that these supposed horrors -- parasitism, predation, decay -- would occur even if there were no humans or sapient nonhumans on the planet.  And arguably, we might suggest that our presence as conscious beings has the potential to make this sort of thing happen less frequently, thereby decreasing the net amount of suffering and misfortune on the planet.

Simply by virtue of existing, and knowing of the sometimes-cruel modes by which the evolved biosphere operates, we are not somehow ourselves being cruel.  One ideological trap in the all-things-must-die paradigm is a failure to distinguish between a noble effort at reducing the destructive effects of one's existence and undergoing an involuntary and permanent loss of sentience. Sentience brings with it responsibility, and the superficially "unselfish" suggestion that one needs to die, like everything else, does not speak to me of strength of character -- rather, it speaks to me of a lack of a sense of self-worth.

Customs such as the avoidance of "speaking ill of the dead" are evidence of a human tendency to equate death with innocence, even vulnerability. No matter what one does while alive, death and oblivion absolve all guilt, all responsibility, and all accountability. I personally have no beliefs in a supernatural afterlife, but for those that do hold such beliefs, it seems that quite a few might take comfort in the fact that at some point, they won't need to wonder anymore how they're going to be judged -- in a sense, this is not much different from taking comfort in the notion of pure oblivion. In either case, there comes a point in existence after which a person is no longer responsible for changing or evaluating their self-made nature or their behavior.

Conversely, as long as a person is alive, they are accountable for their actions and responsible for what they know and how they use this knowledge. I am not one to use "greater good" as an argument, however, I would definitely disagree with those who insist that the development of healthy life extension technologies would inevitably result in social discord and destruction.

One rule I live by, in part inspired by my committment to avoid death for as long as possible, is that of not doing anything I'm likely to regret later on. Anything I do, I figure I'm going to have to remember for as long as I am conscious. I've made a concerted effort to attempt to imagine how I will feel following any particular action -- and how that action may affect my environment. This has nothing to do with any sort of quasi-religious notion of having to "earn" my existence or perform certain actions so as to avoid negative judgement, but rather, a notion of taking responsibility for my conscious existence.

Those who choose to live a very, very long time are going to have to live with themselves for a very, very long time. I see nothing noble in the notion of getting "out of the way" for someone to take your allotment of air and space -- in a sense, this mindset suggests thinking of death as an escape from responsibility. The base assumption that your very existence represents an imposition on reality (and therefore ought to be subject to involuntary termination) serves no "greater good" unless you have no intention of continuing to self-examine and better yourself accordingly. However, as a supporter of healthy life extension measures, I take the position that one can almost certainly have a more positive influence on reality by continuing to live than by ceasing to exist.

A person who considers it necessary and proper to "get out of the way" rather than use his / her accumulated wisdom to help make reality better for all the conscious creatures in it is no more noble than an airline pilot who considers it necessary and proper to jump out of a plane on the assumption that one of the younger passengers should have the chance to figure out how to land.

While there is much merit in learning something from the ground up, on one's own, there are plenty of cases in which experience can serve as a foundation on which much greater discoveries and endeavors may take place. The diversity of human thought and ideology suggests a future society in which the old (and healthy) can instruct and enlighten the young and less experienced, while at the same time taking plenty of opportunity to go off in new directions that would not have been remotely possible without 100 or more years of experience.

Remember that even as our presence might result in choices made that result in some disharmony, we also have the ability to create stunning works of beauty and complexity. Our sentience allows the construction of castles and sculptures and difference engines wrought of Lego bricks. We have learned to identify and protect endangered species, to extend rights to those marginalized in the past, and to in many cases take responsibility for helping create the future we would like to inhabit. Clearly, there is more to sentience and conscious experience and living than mere guilt-inducing destruction. Conscious beings have every bit as much potential to do good as they do to foster destruction.