There was a discussion of learning disabilities on Facebook this morning which reminded me of this:
Like quite a few people, I am dyslexic. Slightly. My first grade teacher discovered this when I could NOT spell 'the' correctly. I'd look at the word and write down teh. Nobody had a name for this problem nor did they know how to handle it in the 1950s. So I muddled along.
Believe it or not, I became a writer and a Librarian.
Now, imagine this. I look at the catalog to find the Dewey decimal number of the book(s) a patron needs and I write it down. Halfway to the bookshelves, I check the scrap paper where I wrote it and I discover that, of course, I have reversed the numbers. At this point, I fake it. Since by this time I have most of the Dewey areas memorized, I simply keep on heading to the Sports section, or whatever, and find the book for the person. (and make another mental note to self that I really, really need to double-check what I wrote down Before walking the person to the bookshelves.)
p.s. Spellcheck has saved me many times since it was invented, but there's no spellcheck for Dewey decimal numbers.