Daniel Kahneman is undeniably one of the best authors today, with his astounding works shedding light on critical issues of what people face today. Kahneman’s book, “Thinking, Fast and Slow” sheds lights on the fundamental aspects of human sociology and cognitive physiognomies. The book’s essential parts take the form of several systems that Kahneman uses to ensure a significant coverage of matters about the human brain and thoughts formation. While there is a firm conviction among people that they know what goes on in their mind, Kahneman, through his book, makes significant attempts to elucidate the irrational functioning of the brain insofar as human thoughts are concerned. The book delineates the astounding biased operation of one’s mind by its capability to withhold diverse things severally and sometimes simultaneously. Kahneman’s book covers, chiefly, the biases of intuition. Accordingly, more than often individuals are prone to make justified decisions based on some factors while their minds are functional. However, there is a general tendency of encountering several hitches, which disorient the manner in which one’s mind handles impressions and feelings. Kahneman seeks to extricate human errors of judgment that dwell within one’s mind, thereby providing useful tools of communication with which individuals can use to improve their ability to detect such inaccuracies. Uninformed opinion, as Kahneman finds, is highly likely to be an effect of the inability to identify errors in understanding. Thus, he proposes a diagnosis that if well carried out, can go a long way to enabling individuals to make sound decisions. This paper will shed light on Daniel Kahneman’s book, Thinking, Fast and Slow, and give a wide-ranging guide of the book as well as shed light on its other reviews from distinguished scholars.