One classic dispute in philosophy can be crudely summed up by two competing bumper-sticker slogans. One is “everything happens for a reason.” The other is “stuff happens.” The first slogan expresses a version of the teleological view—the idea that the world is driven by purpose. The second expresses the non-teleological view—the world is not driven by purpose. It might be a deterministic world or a random world, but what occurs just happens.
Not surprisingly, there are many different theories that fall under the teleological banner. The sort most people tend to think of involves a theological aspect—a divine being creates and perhaps directs the world. Creationism presents a “pop” version of teleology while Aquinas presents a rather more sophisticated account. However, there are versions that are non-theological. For example, Thales wrote of the world being “full of gods”, but did not seem to be speaking of divine entities. As another example, Aristotle believed in a teleological world in which everything has a purpose.
The rise of what is regarded as modern science during the renaissance and enlightenment saw a corresponding fall in teleological accounts, although thinkers such as Newton and Descartes fully embraced and defended theological teleology. In the sciences, the dominance of Darwinism seemed to spell the doom of teleology. Interestingly, though, certain forms of teleology seem to be sneaking back in.
One area of the world that seems clearly teleological is that occupied by living creatures. While some thinkers have the goal of denying such teleology, creatures like us seem to be theological. That is, we act from purposes in order to achieve goals. Even the least of living creatures, such as bacteria, are presented as having purposes—though this might be more metaphor than reality.
Rather interestingly, even plants seem to operate in purposeful ways and engage in what some scientists characterize as communication. Even more interesting, entire forests seem to be interlocked into communication networks and this seems to indicate something that would count as teleological. This sort of communication can, of course, be dismissed as mere mechanical and chemical processes. The same can also be said of us—and some have argued just that.
It is quite reasonable to be skeptical of claims that link the behavior of plants to claims about teleology. After all, the idea of forests in linked communication and plants acting with purpose seems like something out of fantasy, hippie dreams, or science fiction. That said, there is some solid research that supports the claim that plants communicate and engage in what seems to be purposeful behavior.
Even if it is conceded that living things are purpose driven and thus there is some teleology in the universe, there is still the matter of whether or not teleology is broader. While theists embrace the idea of a God created and directed world, those who are not believers reject this and contend that the appearance of design is just that—appearance and not reality.
One reason that teleology often gets rejected (sometimes with a disdainful sneer) is that it is usually presented in crude theological terms, such as young earth creationism. It is easy enough to laugh off a teleological view when those making it claim that humans coexisted with dinosaurs. Also, there is a strong anti-religious tendency among some thinkers that causes an automatic dismissal of anything theological. Given that supernatural explanations do tend to be rather suspicious, this is hardly surprising. However, bashing such easy prey does not defeat the sophisticated forms of non-supernatural teleology.
The stock argument for teleology is, of course, that the best explanation for the consistent operation of the world and the apparent design of its components is in terms of purposes or ends. The main counter is, of course, that the consistency and apparent design can be explained entirely without reference to ends or purposes. To use the standard example, there is no need to postulate that living creatures are the result of a purpose or end because they are what they are because of chance and natural selection. When someone has the temerity to suggest that natural selection seems to smuggle in teleology, the usual reply is to deny that and to assure the critic that there is no teleology in it at all. Those who buy natural selection as being devoid of teleology accept this and often consider the critics to be misguided fools who are, no doubt, just trying to smuggle God back in. Those who think that natural selection still smuggles in teleology tend to think their opponents are in the grips of an ideology and unwilling to consider the matter properly.
Natural selection is also extended, in a way, beyond living creatures. When those who accept teleology point to the way the non-living universe works as evidence of purpose, the critics contend that the apparent purpose is an illusion. The planets and galaxies are as they are by chance (or determinism) and not from purpose. If they were not as they are, we would not be here to be considering the matter—so what seems like a purposeful universe is just a matter of luck (that is, chance).
It is, of course, tempting to extend the teleology of living creatures to the non-living parts of the universe. If it is accepted that we act with purpose and that even plants do so, then it becomes somewhat easier to consider that complicated non-living systems might also operate with a purpose, goal or end. Interestingly enough, being a materialist makes this transition even easier. After all, if humans, animals and plants are purely mechanical systems that operate with a purpose, then the idea that other purely mechanical systems operate with a purpose would make sense. This is not so say that stars are intelligent or that the universe is a being, of course.
There are those who deny that humans and animals operate with purpose and assert that we simply operate in accord with the laws of nature (whatever that means). Hobbes, for example, took this view. On this sort of view humans and the physical world are basically the same: purposeless mechanical systems. On this view, there is no teleology anywhere. Stuff just happens.