In Ericsson’s seminal 1993 paper on the topic, titled “The Role of Deliberate Practice in the Acquisition of Expert Performance,” he dedicates a sect… - Cal Newport

Ericsson notes that for a novice, somewhere around an hour a day of intense concentration seems to be a limit, while for experts this number can expand to as many as four hours — but rarely more.

It’s not just that we’re less clear than we think, but we’re often completely misunderstood. You were sure that you were sending a nice note, while your receiver is equally sure you were delivering a pointed critique. When you build an entire workflow on exactly this type of ambiguous and misunderstood communication — a workflow that bypasses all the rich, non-linguistic social tools that researchers like Alex Pentland documented as being fundamental to successful human interaction — you shouldn’t be surprised that work messaging is making us miserable.

monastic philosophy of deep work scheduling. This philosophy attempts to maximize deep efforts by eliminating or radically minimizing shallow obligations.

Seinfeld began his advice to Isaac with some common sense, noting “the way to be a better comic was to create better jokes,” and then explaining that the way to create better jokes was to write every day. Seinfeld continued by describing a specific technique he used to help maintain this discipline. He keeps a calendar on his wall. Every day that he writes jokes he crosses out the date on the calendar with a big red X. “After a few days you’ll have a chain,” Seinfeld said. “Just keep at it and the chain will grow longer every day. You’ll like seeing that chain, especially when you get a few weeks under your belt. Your only job next is to not break the chain.” This chain method (as some now call it) soon became a hit among writers and fitness enthusiasts — communities that thrive on the ability to do hard things consistently.