Book Summary: The Two Greatest Ideas

Title: The Two Greatest Ideas
Author: Linda Trinkaus Zagzebski
Genre: Philosophy,
Release Date: 2021


Why did you choose to read this particular book?

As part of a book club, I read this book.

Summary of book

The first idea is that the mind can understand the universe, while the second idea is that the mind can understand itself. Before the Renaissance and the emergence of the second idea, humanity embraced the first idea. They believed that the universe is logically structured and that the mind can fully comprehend it. This perspective, known as philosophical realism, suggests that the objects we perceive exist regardless of whether there are minds to perceive them. This belief influenced ethical and political views that emphasized living in harmony with nature and society, while downplaying individual autonomy. However, everything changed with the rise of the second idea, which introduced the concept of the mind understanding itself. This gave birth to the subject/object divide and philosophical idealism. According to idealism, our reality is shaped more by our thoughts and ideas about the world than by the world itself. There are two forms of idealism: George Berkeley’s belief that only the mind exists, and Immanuel Kant’s transcendental idealism, which acknowledges the existence of an external reality but asserts that our minds construct our own reality, which may not correspond to the true nature of things.

Kant’s idealism suggests that our perception of the world may not accurately reflect its true nature. This can be understood by considering colour blindness. If a person with normal vision sees an object as “red” while a colour-blind individual sees it as “green,” it becomes clear that the object itself is neither red nor green. Instead, the perception of colour is a mental property independent of the object. This line of thinking can be extended to other senses like taste, sound, and touch, as well as abstract concepts like space, time, causation, and solidity. It leads us to question whether the world as we perceive it is truly how it exists. Philosophers began to focus more on the subjectivity of our inner worlds rather than viewing the mind as a direct window to an external reality.

Just like the first great idea, the second great idea also gave rise to unique ethical and political positions. These positions prioritize individual self, rights, and autonomy rather than seeking harmony with reality. They contrast with the belief that we are all part of a single, knowable reality that is greater than the sum of its parts. Zagzebeski explores the intellectual history of these two ideas and highlights the conflicts they have created, conflicts that continue to impact us today.

Zagzebeski connects these two great ideas to the political conflicts of our time. She demonstrates that both liberals and conservatives inconsistently prioritize social harmony and individual autonomy across various issues. Liberals may prioritize individual autonomy in pro-life stances while emphasizing social and natural harmony in their views on climate change. On the other hand, conservatives may emphasize autonomy in advocating for gun rights while prioritizing social harmony in their stance on issues like abortion and same-sex marriage.

Zagzebeski encourages us to delve deeper into our positions and show more empathy towards those with different perspectives.

In the final section of the book, Zagzebeski introduces the concept of intersubjectivity, which she considers the third greatest idea. She argues that Western philosophy and science have focused too much on understanding the objective world and our own subjective experiences, neglecting the importance of understanding other minds and how they shape our individual realities. By exploring empathy in psychology, the neuroscience of emotion and sociality, and philosophical reflections on the interconnectedness of our subjective worlds, we can bridge the gap in our understanding of others’ minds and foster more tolerance for differing views in politics.

What stood out for you

A good discussion of these two great ideas

Key Points

The first concept is the belief that the human mind has the capacity to comprehend the vastness of the universe. The second concept is the notion that the human mind can truly understand itself. Interestingly, the first concept sparked a cultural revolution during the first millennium BCE, giving birth to philosophy, mathematics, science, and nearly all major world religions. This concept reigned supreme until the Renaissance, when the discovery of subjectivity profoundly transformed the realms of art and science. The second concept, which governed our perception of reality until the twenty-first century.

What you dislike

One criticism is that it oversimplifies the history of philosophy.



Has the book met its objective?

Yes as an intro to these ideas

What would you change

There was some repetition at times

What type of reader would enjoy this book

A good casual read

Would you recommend this book


Final Verdict:

Read more reviews here: Book Review – The Wise Word

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