I think it’s all about inspiration here. Those that sit at a desk or a cubicle and do vast amounts of work for others, just to make the bucks, are the one’s most at risk of turning their minds into a pile of mush. There are ways to off-set this of course. Day dreaming for one tunes you out of the work mode and feeds the mind. Find a good technique to get your mind out of the office, it really can take you anywhere. If you can’t think of anything to daydream about, looks like it could be too late for you already I am afraid.
The so called 'internet' also has huge potential to offset the degradation of the mind. If you are going to go this route you will need to have the all important screen angle sorted out. Make sure it faces just you and is not visible to curious work colleagues or mean boss’s. If your workplace has banned you from that form of stimulation, you are nothing but a modern day slave ship galley rower and need to make a change soon or risk fading away like the many millions before you.
Post script: Some jobs are so enjoyable that payment just seems like a cool perk to the vocation. I mean you can’t tell me the techi geeks who design computer games are thinking about the cash.
My good friend Seth Rotherham likes to say: “Work is a sideline, live the holiday”.