In a recent post at the evolutionnews.org website (see here), Cornelius Hunter comments on a article by Princeton neuroscientist Michael Graziano in The Atlantic. The article discusses a new theory, known as Attention Schema Theory (AST), which seeks to explain how consciousness arose in living things. According to Graziano:
[AST} suggests that consciousness arises as a solution to one of the most fundamental problems facing any nervous system: Too much information constantly flows in to be fully processed. The brain evolved increasingly sophisticated mechanisms for deeply processing a few select signals at the expense of others, and in the AST, consciousness is the ultimate result of that evolutionary sequence. [emphasis added by Hunter]
Hunter points out that this is rather problematic as an evolutionary explanation of the origin of consciousness since "[evolutionary theory] technically is restricted to aimless mechanisms," but the thinking underlying AST is teleological in nature. In other words, evolution is supposed to be a random process that doesn't aim for any particular goal, but AST implies that consciousness emerged with the goal of solving the problem of too much information (it almost sounds as if "evolution" was acting consciously!).
I think Hunter is right about this, but it seems to me that there is another problem with AST. Keep in mind that AST is being proposed as a theory within the framework of neo-Darwinian evolution. Evolution is a supposed to be a process that deals with the material, the physical--like certain structures within a biological organism. In other words, evolution presupposes materialism/naturalism. And yet, consciousness is not physical or material. Philosopher J. P. Moreland explains the problem thus:
Naturalism is...a strictly physical story. And that is where...[the] most fundamental problem of consciousness enters the picture. If you begin with matter and simply rearrange it according to physical laws by means of strictly physical causes and processes, then you will end up with increasingly different arrangements of--you guessed it--matter. Start with matter and tweak it physically and all you will get is tweaked matter. There is no need or room for consciousness to enter the picture. (The Soul: How We Know It's Real and Why It Matters, p. 76)
No wonder philosopher Colin McGinn asks: "How can mere matter originate consciousness? How did evolution convert the water of biological tissue into the wine of consciousness? Consciousness seems like a radical novelty in the universe, not prefigured by the after effects of the Big Bang; so how did it contrive to spring into being from what preceded it?" (quoted in Moreland, The Soul: How We Know It's Real and Why It Matters, p. 74).
In short, AST fails as a convincing evolutionary explanation of the origin of consciousness because--as Hunter points out--it is based on teleological thinking and because it fails to explain how consciousness, which is immaterial by nature, could have emerged as the result of physical processes acting on matter. This is just another example of how scientific theorizing can get off-track when it fails to grapple with underlying philosophical issues.
Image from cosmosmagazine.com (from Wikimedia Commons)