I had never heard of Walter Oi before he died, but there were some interesting blog posts remembering him that I read. One of them linked to a paper he had written regarding profit maximisation when a company was in the business of selling two different products that were desired in conjunction. Looking at the paper, I noticed the references, the formatting, and I considered that, being blind, he was almost certainly reliant upon someone to type a fair bit of it up for him while he dictated it. There are, I think, three things which we can learn from the existence of this paper.
First, that some people are amazingly clever and productive. His mind was sufficiently keen that someone else could be more productive typing his work than doing work of their own. It's always fascinated me that there are some people whose time is literally worth thousands of pounds an hour; I doubt we're talking that scale here, but it's still incredible to think that while I'd struggle to produce £10 worth of value in an hour, there are people producing hundreds of times that.
Secondly, how much many of us would hate being blind. There are so many things you'd lose the ability to do - reading, driving, exercising unassisted... People are often willing to be accommodating - in Ceilidhs I've danced with a blind girl and with several people who were in wheelchairs - but at the very least it entails a severe loss of independence. Sight is one of the greatest gifts we have.
Finally, the extent to which the lives of disabled people are being improved by technology. A couple of centuries ago it would have been nigh impossible for a blind person to make themself understood except through speech - without the ability to see where on the paper one was writing, you'd presumably end up writing your lines on top of each other. Sixty years ago, one could have used a typewriter: this would take a fair bit of getting used to, and would require someone to read it back to you for editing and to help with the formatting, but would at least give you a clearly written message. Nowadays, you'd just use a voice recognition program on your computer (which would also use voice commands to switch on/off and to navigate between programs) and achieve efficiency close to that of an otherwise equally capable sighted person. Perhaps (stepping into the realms of sci-fi) the future will bring machines which read your brain and translate your thoughts straight to the page and it will make no difference whether or not you can see the external world. One can only dream.