These notes are published as "food for thought." Different views on the subject are possible.
The development of consciousness in human beings cannot be easily explained within the Darwinian theory of evolution. Consciousness is normally considered a by-product of intelligence and therefore it should emerge with a complex enough brain. As the hominids specialised in using the brain to survive, that organ would have developed constantly, increasing in complexity, and producing consciousness as an unavoidable consequence. All what it really took for consciousness to emerge, would be the consistent and prolonged stimulation of the brain. Although this may be true, there are some problems.
- Why humans only have developed a complex brain?
- And why specifically the human beings?
- What evolutionary benefits does brain development provide?
There are no easy answers, but I shall try to present an original position. Since the brain is the product of natural evolution, any living being had the possibility to develop a complex brain. Brains and neural systems are not exclusive of human beings. As a result, if intelligence provided an advantage, then other animals should have developed their brains, at least to form some cognitive capabilities.
Yet, human beings alone have matured their brain to a level not comparable to any other being. The main distinguishing characteristic of human beings, aside from their brain, is perhaps that they do not excel in any physical activity. Endurance, especially endurance running, is a notable feature, but what is its practical advantage? Certainly it can be useful in hunting, when it is possible to run down most of the other species of animals. Yet, this does not protect at all from predators and anyway, the energy and time consumed in running down a prey may just be not the most effective way to achieve that target. Claws and bursts of speed seem most advantageous for that purpose. Endurance is however good for one purpose: mobility. Flight endurance allows birds to move across continents, eventually to make journeys around the world. In the same way, people has the capability of changing environment very quickly if need be. And the generally unspecialised body, which seems to perform "average" in most activities, is ideal to allow the flexibility of fast-changing environments. Or, in this case, it can easily adapt to most environments encountered across its journeys. A flexible, highly mobile body does not require much in physiological terms, but survival becomes a continuous challenge, as new environments, predators, food resources and obstacles make any task a difficult one. The human brain is the solution, rather intelligence. That allows to find repair when needed, to wear a fur, to carry useful tools and resources and so on. If you are specialised in something, then your body naturally is fine-tuned by evolution to avoid dangers and perform at its best. However, if a being is subjected to frequent and rapid environmental changes, then that being needs to understand in order to take decisions that evolution would take in far greater amounts of time.
Brain development therefore benefits the mobile individuals, empowering them with the essential natural features to adapt and be flexible. The aforementioned birds have endurance too, but they seek to move in similar environments, avoiding natural changes. So they do not need a brain to understand new environments, their body is actually highly specialised for flight and their specific environment and none of the two requires any understanding to improve chances of survival.
So, we may answer our questions stating that human beings uniquely "specialised" in mobility across environments. Because of this, the body appears largely unspecialised, but it is flexible. The two essential natural features required for mobility are "good legs" (endurance) and the capacity of understanding rapidly new environments (brain and intelligence). In this view, natural evolution is responsible for intelligence and the complex brain. It also explains why only human beings have developed so much their brain, it is their specialisation feature necessary for their survival. The natural development of the brain to understand farther and new environments also explains why human beings are so attracted by the unknown, a feeling familiar to any scientist.
We come then to the final point: why consciousness occurred? Consciousness is not intelligence, and has no immediate advantages. You can understand an environment without the need to be aware of yourself. And unlike intelligence and endurance, it is absent in the animal world. Apes and other animals seem to have some form of consciousness, but it is far away from what human consciousness is. Whilst intelligence depends on the challenges we have to solve, consciousness can only play a part in creating very complex social relationships. Complex social relationships are very important to humans as well as to apes and other apparently conscious animals. Yet, consciousness often creates more problems in human beings than apparently it solves. Natural evolution should have limited any unnecessary or potentially damaging feature, sticking to the rule of efficiency. In other words, you need eyes good enough to see the environment that surrounds you. More or less powerful eyes would constitute a liability. And so it should be for consciousness. It seems unsatisfactory the suggestion that consciousness is a by-product of intelligence, that reaching a certain degree of brain complexity necessarily brings an advanced consciousness.
There are many ways to explain consciousness within the theory of evolution. For instance, the desire to explore and know may have backfired and be applied to the self or the other human beings. In this case, as in many others, consciousness would have been accidental. But can we accept that something so great as consciousness is a mistake? And if it were a mistake, why evolution did not take remedy?
There is no answer to why consciousness emerged, and perhaps there will never be. One consideration should be made, though. Brain complexity, intelligence and all the other natural features fit well with the theory of natural evolution within the physical world. Consciousness raises the stakes, as it opens the metaphysical world, and it allows humans to clearly distinguish themselves from all the rest. Human beings can perceive beyond their natural senses, they actually are rarely responding to perceptions from the physical world. They are rather in their world of thoughts, symbols and feelings, which are as real as the physical world, but different. Is an idea less real than a desk? Certainly not, but the former is immaterial and cannot be perceived using any sense, nor it can be described in physical terms. Thus, is natural evolution valid in the metaphysical world? Do the same rules apply? Probably not. And that might be why there are problems in viewing consciousness from a strictly evolutionary perspective. In the meantime, the quest for understanding consciousness continues.
15 May 2005
Interesting pages about consciousness:
Center for Consciousness Studies