Sunday, 23 June 2013

Emergent or is it?

Normally the best selling criteria for the systems biology proponents is the idea of emergent properties which ,according to them,dictates the idea that system cannot be studied by studying the property of its components but by looking at the system as such. Also incorporated in this idea is the notion of novelty and coolness. Coolness because you get to laugh at the reductionist who think everything can be known by knowing the property of the constituents of the system. Without much a due, words like "system " and constituents won't make much sense if we don't know what we are talking about,pretty much like what used to happen to me when studying classical mechanics , you know the Hamiltonian of the system and also it trajectory through the configuration space, but what the hell, give me a picture to associate it with. So i present one here.
Imagine a single insect flying here and there looking for food in the forest, and you look at its trajectory and you see no pattern in it, its just like randomly moving from one flower to the other without any predestined path. Now you look at two of them, and you still see their paths are independent and pretty much random. now say take thousands of them or probably million and you see hoards of them moving towards the richer end of the forests and pretty much like a giant organism,a self sustained creature.
Ideas like swarm intelligence and giant organism stem from this very fact that although the constituents are behaving on their own,how they perceive their senses and stuff but together all of them seem to do something more than what one would imagine such lots of individuals doing.
I am here to argue if there is something called emergent behavior or is it really a trick which people realize only when it has amassed in significant numbers. like a story i would like to tell.
Once there was a great emperor in China who wanted the best of men for his personal army to protect him from the Mongolian emperor who was taking the world one at a time ,for the sake of the story lets give him the name of Genghis Khan. Now this emperor asked his general to collect the best men to make his personal army to protect him. General went to the naval chambers and picked Sun Whuz,who was known to be horror of pirates who could drown a ship single-handedly. General in his random stroll encountered a veteran who had killed 16 men of Genghis Khan,again single handedly in war of Hwang Ho. So went the general ,picking up the brightest of men,having heard the story of their talent doing thing single handedly (almost).
The general thought that the if one one good man was gold,10 of them were equivalent to showering gold nuggets. Would the general be so wise? When at last Genghis Khan attacked the empire, and barged through the castle to the throne,these men of protection were falling short of coordination and judgment to do things together as a team and prevent the king from getting killed,which eventually did happen. The moral of the story(if anything) is, the strength of the men was not additive, it was not even complementary and hence the whole was let alone equal,lesser than the sum of  parts.
Alas,the idea of emergent system is very point that the whole is not equal to the sum of parts.It is in some sense like interference of light, the intensity of light from two sources does not add up, it comes with a phase factor, depending on which net intensity could be twice as bright or zero.
I do point out the fact that the concept of emergent property is certainly true but not in the sense of some mysticism, it is just not the property of individual systems ,it is a property of the new system constructed by the individual systems coming together. Like  lines are just having parameters called length ,when arranged in a specific order,they form a triangle,a square which has the property of possessing area and when certain more of such are arranged you get the concept of volume and as you go higher in dimensions, hyper-volume, which makes it impossible to study the behavior of a single constituent as describing the property of the system. and hence  whatever we want to study we must study it at that scale itself nothing below (reductionist approach) or above(statistical approach) that level.
A simpler example is in order.
Seeing these few pages can you predict what property i am talking about








Do you see what i was talking about.
Well if you don't get it,it the stamp on the book , it was always there on the book except that we could not notice it when there were only few pages but as the pages start adding up,we could make out something.
Well,this is basic idea which you should be looking forward to in expecting emergent system not necessarily the same.
 I dont know what else to write except that some people use the very idea of emergent property to support the notion of creationism.Let's have a look.
Emergent systems are characterized by the idea of irreducible complexity that is you cannot study the system by breaking it down. And that idea is also used by creationists in stating the existence of god or perhaps denying evolution, i have problem with both. If you being a scientist know that inference and consistency of evidence implies that evolution did and is happening, you wouldn't really know how to argue back to this statement.Well if you do,its great,otherwise i present my answer,which i learnt from collating ideas my systems bio teacher and also some from Richard Dawkins. The idea of evolution  is to nothing different from building upon the car in your garage and the tools present there,except that the car can produce another one. You got a brand new Lamborghini(lets not argue from where although the answer is still not known but believed to be chemical in origin,the first life not the car).now you have Lamborghini and race it through the tracks and you like its gear and you add another one with the help of the tools in your garage except that the new car you get would already the gear you planted in its mother car. and this can keep on happening time after time sometimes giving rise to a mustang or sometimes a juggernaut or a moped or an aeroplane,whatever might be permitted by shuffling around your tools in garage and occasional thievery from the neighbor's.Sometimes you get a car which wont stop and will run out of fuel and jam,sometimes you would make a car which wont budge but since everyone is doing it,you can expect to see lot of things in say a lifetime. This is the fundamental idea of natural selection.
Now emergent property here means that you got your juggernaut but you cannot find out how it works but disassembling it (well in this case,you can know). So the biological context,irreducible complexity arises because of the action of natural selection on things which were already present and then modifying them.You wouldn't know how it happened until you were there to see it. Or else devise plausible mechanism and model it and see if it converges to what you see in the environment. Its not non falsifiable because you propose a hypothesis and you can do a comparative analysis to check if it occurs in nature.
I think i am a bit confused so i leave it here with a quote from Yogi Berra.
.You've got to be very careful if you don't know where you are going, because you might not get there.
my answer to this was,
Well evolution doesn't care.It has, in principle ,made it everywhere.

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