I read an article late called, “Imagine Earth without People” in "New Scientist" that discussed how long it would take, if all humans were to suddenly disappear, for the last signs of our existence to vanish. The article suggested 200,000 to 400,000 years; though it admitted that the signals we broadcast into space would continue indefinitely. (They did not mention the fate of satellites and lunar probes - many of which would also continue until something crashed into them.)
One feature that I noticed in this article is that the author seemed to have bought into the idea that the human race is a disease - some type of infestation from which the earth needs to 'recover'. The movie, "Matrix" presented this idea to a mass audience - the idea that humanity is a virus.
The author wrote:
Imagine that all the people on Earth - all 6.5 billion of us and counting - could be spirited away tomorrow, transported to a re-education camp in a far-off galaxy. (Let's not invoke the mother of all plagues to wipe us out, if only to avoid complications from all the corpses).
To be honest, my inclination has always been to dismiss such talk as hyperbole born of frustration. However, there are people who take this idea seriously. I have encountered them, for example, when I discuss the colonization of space. Their views range from, "Humans have done enough damage to this planet; we should at least have the decency to leave the rest of the universe alone," to such things as the Voluntary Human Extinction Movement. That is to say, they vote in favor of a human quarantine, where humans are confined to the third rock from the Sun, for the sake of everything else that exists.
So, let me take the idea seriously for a moment.
'Illness' as a Value Laden Concept
I'm going to start with some words about the nature of an 'illness'.
'Illness' is a value-laden concept. Anybody who calls something an illness is saying that it is bad. In fact, 'badness' is written into the meaning of 'illness' in the same way that 'unmarried' is written into the definition of a bachelor. It is not the full definition, but it is an essential part of that definition.
This means that a person cannot have a theory of 'illness' unless he has a theory of 'value'. Before he can say that something is an illness, he has to be able to say that it is bad.
I have a theory of value.
That theory holds that 'badness' concerns reasons for action. To say that something is bad is to say that there are 'reasons for action' for avoiding a state of affairs in which that 'something' exists. To classify cancer as an illness is to say that there are 'reasons for action' for avoiding cancer. Classifying humans as a disease means that there are 'reasons for action' for ridding the universe of all humans.
Desires are the only reasons for action that exist. A claim that there are 'reasons for action' for avoiding a particular state either needs to reference some set of desires, or it is false.
What 'reasons for action' exist for ridding the universe of all humans (or, at least, quarantining humanity someplace where we cannot infest others - the way that small pox is kept locked up in a laboratory)?
Reasons to Eliminate the Human Race
Plants have no reason to eliminate the human race. Plants have no intentional states - which means they have no desires. Therefore, they have no desires that can be thwarted by the existence of humans.
When humans lament the destruction of a forest or even the death of a single tree, the value comes from the human's desire that the forest (or the tree) continue to exist in a particular state. The forest (or the tree) does not care.
As a human desire, we then have reason to ask if there are reasons to promote and strengthen such a desire, or reasons to inhibit such a desire. Actually, I do not need to answer that question. It is sufficient to note how we would answer that question - by looking at whether such a desire tends to fulfill or thwart other desires that exist. Since forests (and trees) have no desires, it has no say in the value of the desire to preserve a forest (or a tree).
Animals have desires. Animals can suffer. Animals have aversions to pain, desires to eat, desires to have sex, (for some) desires for the company of others of their kind and for states in which their offspring are well fed and protected from harm. This is not to say that the parent animal has a desire that their offspring is well fed and safe from harm. Rather, it is a desire for a state which happens to be one in which their offspring is well fed and protected from harm.
A creature cannot desire what it cannot comprehend. No antelope has a desire to fly a P-38 Lightning. No nonhuman animal has an aversion to death, or a desire for the preservation of its species. The last survivor of a species may experience the thwarting of some desire to find a mate, but not a desire to make sure the species continues. Instead, the continuation of the species is an unintended side-effect of animals pursuing what they want - such as eating, drinking, and sex.
The author of this article said that the rest of the animal kingdom would clearly vote us off the planet if they could. I am not so certain about this. Yes, there are some actions that humans perform to animals that animals have reason to avoid. However, there are actions that animals take that other animals have reason to avoid as well. For example, the antelope has reason to avoid the actions of the lion and the alligator. The seal has reason to avoid the actions of the killer whale, and the fish has reason to avoid the actions of the eagle. Life in a state of nature is not all blissful pleasantness up to the point that humans came along.
On the other hand, domesticated animals typically enjoy the benefits of veterinary care, readily available food (so as to keep from starving), protection from diseases and predators, and a quick and painless death.
I am not saying that humans never do evil. There is a lot of unnecessary cruelty. We read in the paper each day of the cruelty that humans are willing to inflict on each other. It is not difficult to imagine the cruelty that they can inflict on animals.
At the same time, there is also unnecessary kindness.
Last, but not least, there are human desires. We also have to ask whether a desire for a future state where no humans exist is a state that is such as to fulfill other human desires generally.
There are clearly a few people who desire a future state without humans. So, a future state without humans will undoubtedly fulfill some desires. However, we still need to ask whether people generally have reason to promote this aversion to the continued survival of the human race.
I am willing to bet that the aversion to human survival is ultimately a desire-thwarting desire. Most of us have desires that require the survival of the human race - at least for a while. We want our children (or the children of our friends and family members) to have a long and happy life. We expect that they will desire the same for their children.
These with a desire that humans cease to exist would act to thwart all of these desires. Therefore, people generally have reason to inhibit the formation of this desire that humans cease to exist. It is, in fact, a despicable position to take.
Fortunately (for now) those who have this disposition tend to be powerless to act on it.
Future generations will likely have reason to wish that we took care of the planet better than we did. Future generations will have to work extra hard to pay off the debt that we passed on to them. They will have less land to work on as coastal areas sink under an ocean rise that we passed onto them as our inheritance. Unless current trends are reversed, they will live in a future world where people are much more inclined to torture others and commit other injustices, because the current generation had such little interest in promoting an aversion to torture and other forms of injustice.
However, it is extremely unlikely that they are going to wish that the human race had wiped itself out in an earlier generation. In fact, I see no more reason to suspect that they will protest the fact that the human race still exists than we are to protest the fact that our ancestors did not destroy the human race. They are likely to be grateful that we did not - as we are grateful that our ancestors did not - bring an end to humanity.
As I said, I would much prefer to ignore this attitude as if it had no significance. However, I have found it common enough to suggest that it actually does hinder projects that aim to preserve and promote human existence. We already have the ‘rapture’ crowd voting for the end of the world. When we add their votes to the ‘humans are a virus’ who should not be contaminating the rest of the universe – or even Earth – without our existence’ crowd, we get an area where the far right (religious fundamentalists) and the far left (environmental purists) can actually agree on a policy.
However, it is a policy that sane people should be ready to condemn, on both fronts.