Reading the comments here, I almost think that there are two classes of people: those of think, and those who don't. I don't quite know what boredom is. Yes, I agree that it takes some mental discipline to keep going on with mental work. I don't disagree that it's easier sometimes not to think than to think. I also don't disagree that all people simply get tired of thinking after a while - after all, we all need a break; mental work is still work. But if most people who, given 15 minutes to themselves, are unable to think and use that productively - that's quite telling. Are they all so seriously tired and worn out that they are all ready to go for a vacation or something? Or can't they think? Perhaps both?