No, this is not a vain effort to sound scientifically astute (I’m not), nor is it a an effort to come up with the most obscure and ridiculous post title in the history of the blogosphere. So what on earth is visual agnosia?
The basic concept is that, when it comes to the biology of how we see the world, there is a difference between sight and perception. When we see something there is apparently a process that takes place – first light falls on the receptor cells in the retina, then a series of electrical impulses pass through a variety of neural pathways and end up in the visual cortex of the brain. As best I can discern, this is where ’sense’ is made of whatever it is that has been ’seen’. Of course all of this happens instantaeously in the course of day-to-day life so it seems counter-intuitive even to think of perception as a process.
Visual agnosia is a condition where the ‘cerebral cortex’ (connected to the visual cortex) is damaged. In this case a person’s eyes would be functioning perfectly as would the visual pathways that communicate sensory perception to the cerebral cortex. What would not be functioning is the part of the brain that makes perception possible.
This person would be able to see objects but would not be able to link up those sights with any stored knowlege or memory of meaning. They might be able to identify and red, smooth circular object with a brown stick pointing out of the top but they wouldn’t recognize it as an apple. McGrath summarizes this phenomenon this way:
Visual agnosia is characterized by an ability to see individual aspects of an object, yet with an inability to make the connections needed to see the object as a whole.
So McGrath draws an analogy between visual agnosia and the dilemma of varying human interpretations of the meaning (or lack of meaning) of nature. It is not enough just to observe nature and assume that its meaning is transparent. It is possible to be able to see all the constituent parts of nature and not perceive the larger reality that they are a part of and this seems to me to be an accurate description of some of the more reductionist forms of scientific materialism.
For me this understanding of how perception works (and can fail to work) reinforces the idea that reality is always interpreted reality. It also raises the possiblity that there might be something ‘extra’ needed in order for human beings to perceive reality correctly. As a Christian I believe that that ’something’ is a faithful response to the person of God – the God in whom all of reality ultimately coheres – and that a true perception of reality is best seen, not as a human achievement, but as a gift.
I am glad you are back to blogging regularly. Your thoughts (and those you pass along) regularly provoke me to thought, and help me begin to put words to some of the thoughts that run around my head.
So thank you.
Thanks for dropping by Brian, I appreciate the encouragement.
So what would you say is the implication of this idea of perception as gift is for scholarship, and science for that matter? What happens if the two conflict(ie. our understanding of thr ‘world behind the world’ so to speak and something proven or disproven, either through scientific experimentation or through logical proofs and methods)? An example might be Gallileo’s conflict with a few literalist and powerful clergy who suggested that the sun MUST revolve around the earth because in Joshua the sun was said to have “stopped in the sky.”. Literally this would imply that the sun is what moves, and its only by implication and analogy that we could say that it didn’t actually, but only the perception of it seemed to show it did. I know this is slightly different than what you were saying, but I think the implication is the same: what happens when what we perceive as our given understanding of the meaning of things conflicts?
I think the idea of perception as a ‘gift’ is a conclusion that I come to based upon my faith in God and my conviction that this offers the best overall explanation of reality. But because it is a conclusion it coheres only within a larger network of beliefs which, taken together, offer the best account (in my opinion) of the evidence. So I’m not sure how much apologetic value it would have to simply say ‘perception is a gift’ and see what difference that makes for science and scholarship.
I think that the scientific enterprise assumes a methodological atheism (and perhaps it must) but its conclusions must be interpreted within a larger explanatory framework. This acknowledgment is what I see lacking in a lot of conversations about science and faith. The meaning of scientific conclusions is not self-evident and I think that an accurate knowledge of perception can remind us that it is often the larger explanatory frameworks that are contested and not specific data.
This is very evident in the example you cite. Of course the issue between Galileo and the church was not specifically about the orbital patterns of the sun and the earth – it was about a total worldview that was perceived to be under attack. So I think that, in the case of disagreements, it is crucial that worldview issues be on the table as, perhaps the most important part of the conversation.
I think I need to read more McGrath, I’ve got a few of his books on my shelf but haven’t read them yet.
One thing I would ask, though, is knowledge specialized? What I mean is that does our “larger framework” of faith change ALL forms of knowledge? You speak of, for example, scientific proofs being interpreted through the framework of faith, but I would simply like to ask, does this in some way change the actual findings of science, or our interpretation of them? And if it is simply our interpretation of them, ought we not to thoroughly know both the arguments and doctrines of our faith, as well as the reasons and proofs given by science? This is exemplified in the debate between creation and evolution. On both sides of the argument you have dogmatic adherents who pressupose the truth of their beliefs in order to justify their interpretation of the science. However, simply addressing the creationist side, they do often dismiss findings in science that I would suggest are alot more definitive than they know, mostly because it is not Christian scientists who are the primary spokespeople, but simply church leaders, who often do not know much about science. There are exceptions, such as Philip Johnson, but the question still remains how we ought to view scientific or psychological findings that appear to contradict our faith, yet seem to be sound in their proofs. I’m thinking McGrath has answers to these questions, since he seems to be one of very few who is well versed in history, science and Christian doctrine, but I’d be interested to know what you think.
I guess on a more basic level the question is also how does our “greater framwork” affect our ability to know God on a rational level. I guess this really strikes at the heart of my own questions about faith: the interaction of faith and reason(Etienne Gilson has a really great book on this “Reason and Revelation in the Middle Ages”). I’ve been learning a lot about rational methods, in particular the importance of understanding logic and argumentation. Since logic, unlike natural science, IS something that can deal with metaphysical questions, and in fact is our most basic tool for these, whether we understand it deeply or not, how could this affect our framework? Is this not something that is continually being changed as we understand more about God, ourselves, and the world around us?
I would also suggest that science does not so much presuppose “methodological atheism” as it deals with a different subject matter than metaphysical questions: I think that this subtle difference can make a huge impact on the interaction between faith and natural science. When we speak of Galileo this does seem to be critical, though I think that most textbooks get it completely wrong. Galileo was a committed Christian and in his “Letter to Christina” he says that his differing with some church leaders is precisely because a few of them cannot see beyond their narrow “world-view”(pun very much intended). They felt that their literal interpretation of scripture proved that his “atheistic” science must be incorrect. That said, he was accepted by most of the leading scientists and intellectuals, just not these. . .well. . .I guess fundamentalists might be the word, literalists anyway. So in this case, their “larger framework of faith” was inadequate to process what a Christian’s science was telling them. I’m sure there was politics involved as well, but we must deal with the written material that we have available to us to judge them. I think the debate between science and dogmatism on both the Christian and Atheist sides of the argument continues to be very much the same today, and the cure, I think, is to understand fully our faith and history of the church, and then also the science that we are evaluating through our framwork. What do you, and McGrath think?