Knowledge isn't free. You have to pay attention ― Professor Richard P. Feynman "Three to four hours a day, five days a week, of uninterrupted and carefully directed concentration, it turns out, can produce a lot of valuable output." says Cal Newport, Cal is Distinguished Associate Professor of Computer Science at Georgetown University and a renowned author. In his bestselling book Deep Work, Cal emphasizes the importance of focus for producing high-quality work. He illustrates this idea with a formula: High quality work produced=Time spent × Intensity of focus He supports this formula with examples from his interviews with some fifty high scoring students from competitive schools. He discovered that the students who scored more studied less than the others, but with more intensity or focus. School Library He also cites the case of Prof Adam Grant, who published seven articles in prestigious journals in 2012 by having uninterrupted sessions of deep work. Newport conclud...