I was going to call this post "On the teleology of informatics" but that just came out sounding way too postmodernist. But I couldn't come up with anything better.
There are a wide spectrum of CP. Our David is one of the more servere case due to his brain damage from a skull fracture. ... Please pardon my morbid thought, (and trust me, this is way more painful for me to bring up than yours) but if human dignity is bound up in our information processing, then there is every little reason to keep David [in] existence, except for medical research purposes.
First, let me reiterate how sorry I am for your tragedy, and that I in no way wish to dissuade you from your faith if it gives you comfort (more on this later). But since you ask...
Even from a hard-core Scientific (capital S) point of view, it is not true that "if human dignity is bound up in our information processing, then there is every little reason to keep David [in] existence, except for medical research purposes." Scientists distinguish between a person and their body. They are not the same thing. This is similar to the distinction that religions make between a person's body and their soul, except that the soul is usually taken to be some extra-physical entity that survives the death of the body. The Scientific point of view is that a person *is* the information stored in their brains. So there is an intimate and mostly unseverable bond between a person and their body. We do not yet know how to extract the information that is a person from the brain that information resides in, except for the little bits that come out in what they say and write and do. At the moment, when the brain dies the person dies, even if the rest of the body that person once resided in might still be alive. The status of such a body is not unlike Henrietta Lack's cancer cells. It is human life, but it is not a person.
Now, I don't know David. I can only base my judgement on what you have told me, and what you have told me is that he is a person with CP. A person with CP -- even severe CP -- is still a person.
How would you find strength in these kinds of life problem?
I have never had to deal with anything even remotely as difficult as what you are faced with, so until I am tested that way the only really honest answer to your question is that I don't know. This is one of the reasons that I take issue with Dawkins and Harris. I don't know their life stories, but from what I can tell they, as I, have been the beneficiaries of life's inequities rather than its victims. It's unbelievably arrogant to sit in an ivory tower and tell someone living in the slums of Calcutta that they should not turn to Jesus or Allah or whatever helps them get through their day.
Also, I occasionally turn to God myself in difficult times. I have been extraordinarily blessed and my troubles are trivial compared to what some people have to face, but I have my challenges and I occasionally have a chat with the Big Man. (I tell him I don't believe in him. He says that's OK :-) Even as a Scientist I recognize that faith is a very powerful force. The thing you believe in doesn't have to be real in order to reap the benefits of believing in it, and I don't want to take that away from anyone (unless they try to force me to believe in it too, of course).
But to answer your question directly: Scientists accept that the world is the way it appears to be to our senses. it is a world of great beauty and joy and and, too often, a world of tragedy and despair. Bad things happen to good people sometimes. People die. That's just the Way It Is.
But though we are creatures of information, we are not creatures of logic. We are not Vulcans, we are humans. Logic is only one aspect of ourselves. We have emotions and passions and desires and internal demons. All those are part of the human condition.
We have the power to make the world better than it would otherwise be. (We also have the power to make it worse.) And we can achieve a limited sort of immortality by taking parts of ourselves -- little bits of the information that lives in our brains -- and making them resident in other brains through writing, talking, and generally being known by other people. As long as David is remembered and loved, part of him is still alive in *your* brain (and now, mine, and everyone else who is reading this). In this way we sow the seeds of our souls.
I find my strength by waking up every day marveling at how privileged I am to be a part of this grand adventure we call reality, to be present here, now, and to witness and participate in all the incredible, marvelous, and occasionally terrible things happening here. Whether this will turn out to be enough when the time comes for me to really be tested I won't know until I get there. I hope it is. It's all I have.