Only 4 Hours of Creative Power

diminishing returns after three or four hours.

I perceived anything more than 4 hours of work as a problem. I had conditioned myself to view anything more than 4 hours of work as abnormal. Few people do this. Most people label this lifestyle as “impossible” and then it becomes so. If I had never registered anything more than 4 hours of work as a problem, my mind would not register opportunities

K. Anders Ericsson found that experts' capacity for deliberate practice was limited to about four hours per day, due to both cognitive and physical fatigue. Like deliberate practice, deep work is also cognitively demanding, so it stands to reason that both share similar limits.

My recommendation is to block four hours a day. This isn’t a typo. I repeat: four hours a day. Honestly, that’s the minimum. If you can do more, then do it.