In this chapter, Yuval Noah Harari delves into the transformative period known as the Scientific Revolution, which began in the 16th century and marked a pivotal shift in human thought and understanding of the world. Harari argues that the foundation of this revolution lies in the acknowledgment of human ignorance, contrasting sharply with previous eras where knowledge was often seen as complete and static.

Harari posits that prior to the Scientific Revolution, most human societies operated under the belief that they knew the world and its workings quite well, relying heavily on tradition, religious dogma, and ancient texts. However, the Scientific Revolution introduced a new mindset that embraced uncertainty and the idea that there is much still to learn. This shift encouraged individuals to question established beliefs and seek empirical evidence, leading to a more dynamic and exploratory approach to knowledge.

One of the key components of this revolution was the development of the scientific method, which emphasized observation, experimentation, and the formulation of hypotheses. This method allowed for repeated testing and validation of ideas, fostering a culture of skepticism and inquiry. Harari discusses influential figures such as Galileo Galilei, who challenged the geocentric model of the universe, and Isaac Newton, whose laws of motion and universal gravitation laid the groundwork for modern physics.

Harari highlights how this newfound approach to knowledge not only advanced scientific understanding but also significantly impacted technology and society. The recognition that human understanding is limited spurred innovations that transformed industries, from navigation and astronomy to medicine and agriculture. This period saw the birth of new technologies, such as the telescope and the microscope, which opened up previously unimagined realms of knowledge.

Moreover, the chapter addresses the consequences of this shift. As humans began to understand the power of knowledge and technology, they also recognized their ability to manipulate the natural world. This realization led to unprecedented advancements but also raised ethical questions about the consequences of such power. Harari warns that while the Scientific Revolution has brought vast benefits to humanity, it has also contributed to existential risks, such as environmental degradation and the potential for technological misuse.

In summary, 'The Discovery of Ignorance' illustrates how the Scientific Revolution redefined humanity's understanding of knowledge and ignorance, leading to a culture of inquiry that has shaped the modern world. Harari emphasizes that embracing uncertainty and the unknown has been a crucial driver of progress, fundamentally altering not only our relationship with knowledge but also our place in the universe.