Purpose/3. Looking For A Purpose/Can We Use Life's Purpose?
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Again, the short answer is no; life exists, and its various forms and capabilities change, as shifting environmental conditions favour first one, then another, chance mutation. And that’s all that appears to be happening, as generation after generation meanders its way between birth and death. Biologists do not think that life is on a journey to anywhere. Evolution, they say, is natural selection and survival of the fit, nothing more.
Some two centuries ago, Reverend William Paley wrote that life’s complexity necessitated a creator (saying that, just as a found watch would require a watchmaker to explain its existence, so, too, do the complexities of life require a Maker). Although the concepts of mutations and natural selection readily explain how simple becomes complex over time, Paley’s misconception still exists. This impelled Richard Dawkins to write a book to put an end to this mystification.[5] Dawkins’ text reminds us that although complex life might seem designed to non-biologists, it is simply the result of many mutational advantages being piled one upon another, generation after generation—the successful remnants of environment-surviving adaptations.
Most biologists maintain that life provides no evidence of being directed toward a purpose of any kind. However, they usually have no reason to look much beyond the collection and analysis of facts, and the formulation and testing of theories (this, after all, is their chosen mission in life). But we do have a reason to look further. It behooves us to take a second look at what is known about the origins and development of the biological universe, to see if a purpose might be hidden within the larger picture.
At least two factors that most biologists don’t usually concern themselves with can be added to our considerations. First, as discussed earlier, we can be fairly certain that life exists in many forms, all over the universe. Second, if life is so prolific (and if scientists are likely to be able to construct it in the laboratory in the not-too-distant future[6]), then life itself may be nothing very special.
But, what might this be suggesting? If anything, it seems to be saying just the opposite of what we might like to hear. The probable abundance and possible triviality of life seems to imply the lack, rather than the presence, of a purpose.
If life’s existence and behaviour seems purposeless, then let’s see if life’s beginning shows signs of being purpose-directed.
We earlier mentioned what is known about life’s beginning. As far as we can tell, it is simply a matter of physical laws giving rise to chemical molecules that interact, with some of these interactions eventually creating molecules that develop into living entities.[7] There’s no more purpose to be found in such a process than there is to be found in the mere physical presence of the molecules that assemble during that process. The presence and behaviour of all matter is just another result of the presence and behaviour of the universe, and can have no more built-in purpose than the universe itself has.
Well, if the past and present tells us nothing about life having a purpose, then there is only one other place to examine—the future. As we have just mentioned, biologists usually say that they can predict nothing about life’s possible future. They know the mechanics of evolution; the fittest generally survive to parent fit offspring in greater abundance than those less fit. This behaviour doesn’t have to go anywhere; it need have no future other than to favour life’s continuation. In fact, the whole process of evolution, as it is usually described, appears to be a very laid-back process: evolve when conditions change, otherwise stay the same.
But, if we dig a little deeper, we do actually find that something more may be happening. Let me elaborate.
Evolution itself seems to be evolving. Evolution, we know, depends upon the occurrence of one or more chemical or physical happenstance’s that reshape a few of life’s molecules, which then occasionally give rise to descendants better fitted to survive environmental changes. But, this process seems to have become more than solely accidental in advanced animals. Evolution, once a passive occurrence, now occasionally seems to be an active one.
Active evolution involves two events. The first event is always passive: the occasional, random, unavoidable incident that produces a DNA nucleotide change in sperm, ovum, or zygote. A genetic mutation, which (together with its outcome—good, bad or inconsequential) will be carried into descendent generations, should they survive. These descendants may, or may not, be able to utilize this change.
Natural selection tells us that the environment provides the criteria that determines if the inherited change will be beneficial or harmful (dark stripes help to camouflage a zebra in dappled woods, for instance; they may make the animal visible to predators on sunlit plains. Thus, whether a gene mutation helps the animal to hide and survive to procreate depends upon where that animal lives.) However, there can be more going on than just passive use of an inherited feature.
Sometimes the modification to a body structure or system is passed on but lies dormant, unused, perhaps eventually to atrophy from neglect. However, occasionally, the evolutionary process is taken to a second level. Some circumstance (almost always an environmental change) causes the organism to discover how a latent ability might put to use. But, only organisms capable of learning can experience this second step, as will be illustrated.
This two-step evolutionary process seldom takes place in one generation. Mutations that are immediately beneficial are those that do not require learning anything new. Millions of these have occurred throughout life’s evolution—for example, more appropriate body structure, more efficient energy conversion, more attractive plumage, more effective camouflage, etc. These and other such changes benefit with little or no learning curve to conquer. But some parental DNA mutations bring no immediate benefit (or penalty), and these may be passed on unused and un-noticed through many generations. Only when an environmental change offers a niche where these changes might be put to profitable use, may they benefit the bearer. Thus, for example, the uses to which an opposable thumb may be put, or the advantages vocal chords offer language users, must be learned before they can benefit the possessor. Steven Pinker provides an example that illustrates how an ability most take for granted is actually the result of learning how to use an inherited capability.[8] He notes that we are able to see stereoscopically because we grow two, spatially separated eyes, but we each must first train our brain to use them efficiently, and then train our mind to interpret what has been seen. Bear in mind that eyes evolved from light-sensitive cells. When these first developed, no creature possessing them would “know” how they might best be put to use; each slight advantage would have to be discovered, then experimented with, to learn how to interpret the new perceptions. Evolved change by itself is insufficient in such cases.
“Learn” is an active verb, and learning occurs in animals, but not in plants. Animals use their brains and minds to direct their bodies to obtain food and mates, and to avoid predators. What an animal learns[9] and puts into practice can be copied by peers, and by offspring as they emulate their parent’s behaviour. Learned beneficial changes in both mental outlook and physical ability are thus passed on to successive generations.[10]
Simple organisms like plants have not been able to evolve in this manner. Thus, the evolutionary process has itself evolved over time. In its original form, evolution benefits (or harms) future generations without their active participation. But in its later form, evolution can be a two-stage active process that operates only if animals learn how to take advantage of latent abilities.
Recently, evolution added a third capability and level to its repertoire: it can now plan its own future. Let me explain.
Two things happened after humans learned how to speak and write. First, we dramatically increased the speed at which we acquire knowledge, adapt, and change our behaviour. We learn how to extract metals, then build tools and weapons. We learn about genetics, then breed hardier crops and livestock. We learn about fats and cholesterol, then modify our diet. We learn how to survive in space, then go to the moon. What one discovers, others put into effect—increasingly within the same generation.
Second, we became able to plan our future. We have learned how to apply our knowledge to envision a desirable future, then chart a path toward that future. That is how we reached the moon; that is how we might one day reach other planets.
In essence, we now use our third-level thinking ability to consciously consider what the future holds possible. We then use it again to plan the actions necessary to obtain our desired goal.
This ability, I contend, is significant enough to be thought of as a third-stage in the evolutionary process. We have evolved to the stage of being able to take charge of—to be responsible for—our own future. Indeed, humans are verging upon the ability to take control of evolution itself. In short, we are no longer animals to whom change simply happens, or that must learn to take advantage of a latent ability before we can benefit. We have now become animals that can use words to select, far ahead of time, the kind of benefits we want evolutionary change to produce: we can then produce that change.
Is it not ironic that, just as we are learning how to plan and achieve our own future, this future can seem meaningless? If the universe and life exist with no discernible purpose, then everything subsumed within these two concepts also lacks purpose. No purpose, ergo, no meaning. What are we to do?
The answer is clear to me. If neither the universe nor life itself evince a purpose, if there is nothing anywhere that provides rational and universal direction and meaning, and if, as has been many times stated, we simply must have a purpose if we are to make decisions rationally, then we must invent one. To avoid stagnating in a moral quagmire, we must formulate a proxy purpose.[11] Our history of developing religions when searching for nonexistent answers demonstrates that we have done this many times in the past. We can do so again. Therefore, if, as concluded in Chapter Six, the invented purposes of past religions can no longer guide our contemporary moral decision making, then it is time to contrive a new purpose that will.
The question, nevertheless, remains: what purpose do we devise?
