It&#x27;s interesting to me it has to be stated at all to be honest. When I don&#x27;t sleep my productivity plummets, and it&#x27;s pretty easy for me to make the link. Even the difference between 7 hours and 8 hours makes a noticeable impact.<p>I sometimes wonder if these kind of first hand experiences are something that should be a part of the education system, such as depriving yourself of sleep and recording the results, or exercising on and off for several weeks and recording your mood, etc. I find this kind of self experimentation highly informative, and these days I can easily &#x27;feel&#x27; the effects of drinking&#x2F;smoking&#x2F;dieting&#x2F;exercising&#x2F;etc on my well-being and mood, which in turn gives me a lot more willpower to see things through when I can logically infer the cause of bad feelings&#x2F;moods and know they are temporary.