Really? In the few books I've read I've heard quite the opposite - that it is easier to remove components than to add them. Indeed having too many 'components' or being too 'complex' can actually be damaging.
Does being more complex mean being more evolved? I would say no.
Once certain components become superfluous, then producing them requires an unnecessary expenditure of energy, nutrients and processing time. Removing them then becomes evolutionarily adaptive. Even in those situations, what often happens is that the superfluous components become adapted to serve some other purpose.
That, crudely speaking, is what most likely happened in the evolution of a lot of cascade processes. A good example is the vertebrate clotting cascade. One of the original clotting proteins got gene-duplicated, resulting in two copies of the same gene, one of which was thus redundant. Instead of the redundant copy being destroyed, it gets mutated so that a clotting cascade is created. (I'm explaining this very badly - it's one of the principal examples in
Finding Darwin's God, which has a much better explanation.)
The point is that it's logistically easier to add and modify components than to cut them out. To me, complex structures like the eye are not really all that striking examples of evolution. What really grabs my attention are cases of strong
simplification. The prime example is the reproductive cycle of the anglerfish - the male loses all autonomy and basically becomes a pair of gonads attached to the female. How on earth did that happen? How and when did evolution decide (I use an anthropomorphic metaphor) that the entire adult life of the male was just so much scaffolding that could be done away with to create a more efficient life-cycle?
I like your answer, even though my own opinion is quite different. I believe (but cannot prove
) that there is some intrinsic purpose to nature - although what it is I cannot put my finger on.
This idea came from another quote from 'What we Believe but Cannot Prove', this time by Robert R. Provine:
The null position [that consciousness does not play a significant role in human behaviour] is an antidote to philospher's disease - the inappropriate attribution of rational, conscious control over processes that may be irrational and unconscious.
In other words, how can we get meaning and direction from a process which is inherently meaningless and blind?
A ball rolls along a grooved track: where does it stop? The process is inherently meaningless and blind. But number the grooves and install a casino around the roulette wheel, and suddenly the inherently meaningless and blind process has a whole lot of meaning to the crowd of gamblers and casino operators.
I think systems inherit meaning by interacting with a wider system that imbues meaning. For example, from the perspective of a flower, its color is simply the spatial distribution of certain pigments; but when a bee sees that flower, it sees "meaning" - enough at least to know where to find pollen - and when a woman sees that flower she sees even more "meaning". This last meaning would be incomprehensible to, say, a dolphin (an intelligent animal in itself!): the meaning is not intrinsic to the flower, or even the image of the flower, but rather resides in the interaction between the flower and human society.
How, then, does evolution create systems that imbue meaning? It does so because the specialization of the nervous system is adaptive. Meaning is semantic shorthand. It is a way of attaching lots of information to what may be a physically simple object. For example, a rose, though it is just the reproductive organ of a particular thorny plant, carries with it so many of the love stories and ideas of Western civilization. And this applies in a simplified way as well to animals: when a bee sees a rose, it does not just see a particular visual pattern, it sees a place to find nectar for the hive. In its own crude way, it has added information (contained in its genes) to the physical symbol that is a rose, and has acted appropriately.
So, if evolution indeed tends towards nervous complexity, then evolution tends towards the complexity of systems that imbue meaning. Ironically, there is no meaning in that process itself! Does sentience itself have a meaning? Does it mean anything that I have a particular evolutionary theory of meaning, that evolution has given rise to a life-form which can contemplate what meaning might possibly be attached to evolution itself? The theist answer, of course, is that at this point God Himself steps in and imbues meaning to our lives on Earth, and by extension to the creation which we have in our own halting ways seen meaning in.
But then we have a problem. Where does God Himself derive His own meaning? What gives God His own purpose? Either God derives His meaning from some higher system - in which case He's not much of a god - or God derives His meaning from Himself - in which case we humans might be capable of replicating that nifty trick, as in fact we often do on a personal scale. We have stumbled upon a philosophical version of Euthyphro's dilemma, and the answers that work there will largely work here.