by Marcus Loane
I am using the word purpose in a broad philosophical sense here. What is the purpose of an asteroid? What is the purpose of sand? What is the purpose of a universe? What is the purpose of me writing this? What is the purpose of a bird's wing?
The last two questions have an answer. The purpose of me writing this could be answered in terms of motives and folk psychology. The causes of me writing it could be answered in terms of sociobiology or my upbringing, my education, the people I've met, the culture I have been immersed in, my genetic predispositions and the brain structure resulting from these factors. An explanation can be given where my consciousness is important or where it is not relevant. The explanation could regard me as an organism responding to environmental stimuli in the only way it can.
The purpose of a bird's wing is to allow it to fly (ultimately to help it to feed, avoid predators and reproduce). There is a purpose there without any consciousness involved. There is a kind of "free floating" rationale to the shape of a bird, or a slug or a tree. Biological evolution created the purpose, the rationale of a bird's wing. When examining parts of organisms: wings, claws, hearts, brains, leaves, roots, it seems natural to ask what they are for. We assume they have a purpose. That is a reasonable way of talking. Evolution puts the purpose there by weeding out the variations that don't work as well.
Our own thoughts may be produced by a similar algorithm running in fractions of a second inside our skulls. The algorithm weeds out the nonsense (by examining previous matches between thought and sense data) and what is left is purposeful and meaningful. This view sees the meaning as coming from the algorithm. This could become a general explanation of where meaning comes from anywhere in the Universe. Rationale emerges from successive rounds of replication with variation and selection, whether it is acting on genes to produce organisms that seem designed, or on neural activation patterns to produce thoughts that seem designed to fit what is happening to the observer.
Solving a philosophical puzzle
This theory may put to rest philosophical debates that have been going round in circles for millennia. Philosophers like to talk about intentionality. In philosophy it means "aboutness", so thinking "horse" is about a horse out there in the real world. There is a connection between the thought and the real object and philosophers thought this "invisible link" very mysterious, almost magical.
Now an organism has an apparent design that fits its environment - the evolutionary algorithm creates the fit, the connection between the product and what is out there. Similarly, if thought production comes from a real time evolutionary algorithm running in a brain, it is the algorithm that creates the fit or connection between a thought and the outside world. This theory can explain philosophers' intentionality. The "invisible link" is in the fit, like a key fits a lock. We know that a Darwinian algorithm can create a fit/match between what it makes and what is out there in the environment.
It created the streamlined shape of a fish to match the watery environment that it gets propelled through.
Our immune systems have their own separate, speeded up Darwinian algorithm (that runs in a time scale of days) which creates a match between the antibodies it makes and the invading antigen. The latter is a well studied and understood process showing the creativity and capability to generate novelty that an evolutionary algorithm possesses.
Neuroscientists are now seriously considering that the brain also has its own similar algorithm (that runs in a time scale of seconds) which can generate novel thoughts and behaviours when presented with new external stimuli. At the heart of it is random variation of candidate thoughts plus competition between them over many rounds, all invisible to introspection. The "winner" becomes the consciously experienced thought. Incidentally this is the only natural explanation I have come across that is able to explain human creativity, and perhaps even the sensation of free will (it explains what the oft postulated "hidden variables" are). It is not very flattering but our individual creativity and sense of free will could be due to randomness followed up by selective processes. At least that would mean our thoughts and behaviour are not completely predictable. Results of some experiments can be explained by this hypothesis but not by the traditional view of some ghostly observer, so there is already some evidence for it.
To reiterate the similarities, an evolutionary algorithm running over millions of years creates the fit/connection between an organism and its external environment - "knowledge" about the environment is encoded in the shape and functions of the organism. For example a bird's wing contains "knowledge" about aerodynamics. In the case of an evolutionary algorithm producing thought, the match is between the internal organisation of a brain, ie. a brain state, and some condition out there in the world. Knowledge, using its more conventional meaning, is a brain state that matches (is about) something out there. How the philosophers' "aboutness" comes to be, is solved. Henry Plotkin's "Nature Of Knowledge" elucidates on this matching of internal organisation of organisms or brains with external features of the world. He suggests that all knowledge (in its expanded meaning) is an adaptation produced by a Darwinian algorithm.
It is very common in science for more and more to be explained by ever fewer basic principles. Successive rounds of replication with variation plus selection is a basic process that has the potential to explain where knowledge, rationale, meaning and purpose in all its forms (conscious or free floating) comes from.
Some physicists have speculated that our universe was produced by a replication process. The speculation is that there is some larger system, the Metaverse, containing universes which have different initial configurations (which entail such parameters as strength of gravity or mass of a proton for example). Our universe has just the right initial configuration to develop into one that gives rise to black holes. Black holes are points in space that swallow anything that gets too close to them. There are many similarities in the physics of the Big Bang and that of black holes. Black holes are points where time and space end and it is thought that they may produce other big bangs and hence other universes. Our universe would be giving birth to other universes by making black holes. Any universe that just happens to have an initial configuration that lets it produce more universes is a replicator, and will become more numerous than other types. Our universe would be one of the common ones.
Note: the idea described is not strictly an evolutionary algorithm. There is no competition between universes (selection) and it is not clear if there is variation - does our universe make identical copies of itself or are there random alterations to the initial settings of each offspring?
All the idea does is suggest that our type of universe, which appears remarkably fine-tuned for black holes, stars, and life, is a very common type among many others.
Dr Lee Smolin has expanded on the idea and suggested that the baby universes bud off (from black holes) with slight variations in physical constants from our parent universe, so this makes the process closer to an evolutionary algorithm. This would mean that our universe could be said to have a purpose the way a bird's wing has a purpose. The purpose of the universe would be to reproduce itself and the rationale is free floating. Dr Smolin has suggested ways to indirectly test his idea so it is reaching the status of scientific hypothesis.
Purposeful Universe fantasy
While in speculative mood, I will add my own fantasy to mull over. It is possible that with sufficient intelligence a life form can learn enough about how a universe works, that it becomes capable of creating universes itself. We humans have already started thinking about it and a physicist has produced a paper on how to make a universe in the lab. It is only at the theoretical stage but who knows what the future will bring? If we reached a time when we could create universes with different physical laws I think we would strive to make one that could produce life. Now any universe that just happens to have the right initial configuration that eventually leads to intelligent life evolving, will have a chance of reproducing itself by this route. The intelligent life includes physicists that help the universe reproduce by doing dangerous experiments. This means that the Metaverse becomes populated with more universes that are capable of evolving intelligent life than those which cannot. It also suggests that our universe was created by a sentient being to produce us or something like us. The theologians should be delighted. However they may be dismayed to infer that the Creators evolved just like us and could be just as imperfect, and we too may become the Creators of a Universe. Under this scheme our universe has the free floating purpose of being there to reproduce itself and also the conscious purposes attached to it by its sentient creators. Remember, this is just fantasy but fantasy can be useful in opening up new ways of thinking.
Evolutionary algorithms giving rise to purpose
|Evolutionary algorithm||Gives rise to the rationale/purpose of...||Status of theory|
|Biological evolution||Organisms' structure and instinctual behaviours||Mainstream science|
|Human immune system||Appropriate antibodies||Mainstream science|
|Cultural evolution||Memes - fashions, religions, ideologies||Hypothesis/ true by definition?|
|Thought production algorithm||produces personal knowledge and purposes||Hypothesis|
|Metaverse evolution||Our Universe||Very speculative|
If there are evolutionary algorithms running in all these areas then some are nested within each other. Taking those that are already known first; the biological evolutionary algorithm (producing humans for example) itself evolved another evolutionary algorithm (the immune system) nested within it. We know it has done it once so it is not as large a stretch to suggest that another algorithm could have evolved and be running in brains to produce thought.
If the cultural and thought production evolutionary algorithms are confirmed then there is a three layered nesting of algorithms. The biological evolution produced the brain that in turn runs the thought production algorithm, which across many brains, provides an environment for cultural evolution to evolve the spread of ideas. That is three replication-with-variation-plus-selection processes being executed on top of each other and is the best explanation yet of how we can have knowledge, and where purpose comes from.
Summary: An algorithm using imperfect replication with selection creates a fit between its product and some aspect of the environment, like a key fitting a lock. The key embodies knowledge about the lock. The key has a meaning and a purpose because of how it relates to the lock. My view is that ever more complex implementations of this principle with perhaps many such algorithms nested within each other is what gives rise to knowledge, meanings and purposes.
*While the key and lock is a simple example to illustrate quite a difficult concept, a key fitting a lock is literally created in nature by evolutionary algorithms. The immune system uses a lock and key like mechanism by which antibodies can lock on to foreign invaders. Enzymes and catalysts are also molecular locks that accept molecular keys.