-This post is excerpted, with changes, from the book Darwin, God and the Meaning of Life by Steve Stewart-Williams - available now from Amazon.com, Amazon.ca, and Amazon.uk.

Evolutionary theory answers one of the most profound and fundamental questions human beings have ever asked themselves, a question that has plagued reflective minds for as long as reflective minds have existed in the universe: Why are we here? The question was answered in 1859 by the English naturalist Charles Darwin, and the answer can be stated in just six words:

We are here because we evolved.

For what purpose are we here?

What I'm going to argue in this post is that evolutionary theory provides an answer to this sense of the question as well. But before I get to that, let's survey some of the interesting answers that people have given to the question of the meaning of life over the ages.

Religious Answers

A lot of answers have come from religion. Among the views associated with the Western religions is that the purpose of life is...

to serve or submit to God (the word "Islam" means submission)

to fulfil the purpose for which God made us

to gain entrance to heaven

to look after the planet

to convert people to one's religion

Eastern answers have a very different flavour. They include such ideas as that the purpose of life is...

to break free of the cycle of reincarnation and karma

to achieve enlightenment and be extinguished as an individual conscious entity, or merge back into some kind of collective consciousness

Secular Answers

There are also various secular or religion-neutral answers; I googled "meaning of life" and came up with some very cool quotations on the topic (I particularly like the fourth):

Kurt Vonnegut: "We are here to help each other get through this thing, whatever it is."

The Dalai Lama: "The purpose of our lives is to be happy."

Ralph Waldo Emerson: "The purpose of life is not to be happy. It is to be useful, to be honorable, to be compassionate, to have it make some difference that you have lived and lived well."

Nelson Henderson: "The true meaning of life is to plant trees, under whose shade you do not expect to sit."

H. L. Mencken: "You come into the world with nothing, and the purpose of your life is to make something out of nothing."

Monty Python: "It's nothing very special. Try to be nice to people, avoid eating fat, read a good book every now and then, get some walking in, and try to live together in peace and harmony with people of all creeds and nations."

Another non-religious idea I'm very fond of is that the purpose of life is to create something that no one else could have created, and thus to bring into existence something that wouldn't exist if you hadn't existed. In any case, let's now turn our to the question of what evolutionary theory brings to the party.

Evolution and the Meaning of Life

First, I should make clear what I'm not going to argue. I'm not going to argue that evolutionary theory implies that the meaning of life is to survive and reproduce, or put forward our , or enhance our fitness or anything like that. Evolutionary theory tells us where we came from, not what we should do now that we're here. So what does the theory imply?

To answer this, we need to look at some background ideas. Traditional explanations for the "design" found in organisms (e. ., the design found in the human eye) involved a style of explanation known as teleological explanations. Teleological explanations are framed in terms of purposes and future consequences. For example, we might say that the giraffe has a long neck for the purpose of feeding on leaves high in trees. From a Darwinian perspective, this is actually the wrong answer. In fact, it's not just the wrong answer; it's the wrong kind of answer to questions in biology. The giraffe does not have a long neck in order to achieve this or any other future goal. It has a long neck because long-necked giraffes in the past were more likely to survive and reproduce than were their short-necked counterparts, and thus long-necked giraffes were more likely to pass on the genes contributing to their longer necks. This point is crucial to a proper understanding of evolutionary theory: There is no teleological explanation for long necks, only a historical explanation. A historical explanation focuses not on future effects, but on the past circumstances that brought adaptations about.

With this in mind, let's return to the question of the purpose of life. You probably already know where I'm going with this. We've considered various suggestions about why we are here: to get to heaven, to help other people, to propagate our genes. These are all teleological answers. On an evolutionary view, these are not simply wrong answers to the question; they are the wrong kind of answer. Darwin showed that we don't need to posit any kind of foresight or future-directed purpose underlying the apparent design in the biological world. In doing so, he showed us that there is no reason to think that there is a teleological answer to the question of why we are here. There is only a historical one.

Thus, evolutionary theory provides answers to both senses of the question of why we are here, the historical and the teleological:

Historical: We are here because we evolved.

Teleological: We are not here for any purpose.

That's right; that's what I'm saying: We are not here for any purpose. Of course, we all have our own little purposes in life that we choose and that make our lives meaningful in the emotional sense. But if we're interested in the question of whether life is ultimately meaningful, rather than whether it's potentially emotionally meaningful, well after Darwin, there is no reason at all to suppose that it is - there is no reason to assume that life has any ultimate meaning or purpose.

A Gloomy Conclusion?

This might sound like a gloomy conclusion, especially for those of us who were brought up believing that there is some overarching purpose to the universe or meaning to our lives. The first point to make is that, even if it is a gloomy conclusion, this says absolutely nothing about whether it's a true or an accurate conclusion. But as it happens, it's not necessarily such a gloomy conclusion anyway. There's an important distinction between the idea that life is ultimately meaningless (which is an abstract, philosophical conclusion), and the feeling that one's own life is meaningless (which is a symptom of ). Most people can live perfectly happy lives even while accepting that life has no ultimate meaning , at least once they get used to the idea. Some even cheerfully accept that life is meaningless and view it as amusing in a strange kind of way - a cosmic joke but without a joke teller.

This is an issue that the existentialist philosophers grappled with and agonized over, and a lot of them came to the same conclusion that I have: that life is ultimately meaningless. But many found a silver lining in this cloud. They concluded that, if there's no meaning or purpose imposed on us from outside ourselves, then that leaves us in the position where we are free to choose our own meanings and purposes in life, both as individuals and as a species. And for many people, this is a deeply liberating idea. I'll leave the final word to the philosopher E. D. Klemke, who wrote...

"An objective meaning - that is, one which is inherent within the universe or dependent upon external agencies - would, frankly, leave me cold. It would not be mine... I, for one, am glad that the universe has no meaning, for thereby is man all the more glorious. I willingly accept the fact that external meaning is non-existent... for this leaves me free to forge my own meaning."

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