Once in a while I experience something akin to critical aphasia, when words suddenly lose meaning.
You know this.
When you've been writing or reading or working for some time, suddenly a common combination of letters becomes exotic, mystifying and dangerous.
You question the symmetry of "ladder", the unusual sensuousness of "maize", the reversed perspicuousness of "proposal" and wonder just what the hell "thorough" is all about.
Letters swim around the page and you feel like an idiotic intruder, getting a painful glimpse of what it must feel to be illiterate, to be void of words.
When this happens, it is time for a smoke.