Why We Think What We Think
By Turi Munthe · Published by Penguin
The research behind Opinion DNA — a deep exploration of how genetics, geography, history, and biology shape our beliefs, values, and the way we see the world.
The science of why we disagree
We like to think our opinions are the product of reason and evidence. The truth is stranger. Our beliefs are shaped by forces most of us never examine — from the structure of our taste buds to the farming practices of our ancestors, from the density of our neighbourhoods to the microbes in our gut.
Drawing on extensive interviews with neuroscientists, behavioural psychologists, social scientists, and philosophers, Turi Munthe traces the hidden architecture of human opinion. The result is a book that changes how you understand yourself, the people around you, and the arguments that define our time.
This is the research that led to Opinion DNA — the 48-dimension assessment that maps your personality, values, and meta-thinking. Read the book to understand the science. Take the test to see it in yourself.
What the book explores
The biology of belief
How genetics, neuroscience, and physiology shape what we believe — from pain sensitivity to political orientation, from taste perception to moral intuition.
The geography of opinion
Why where you grew up changes how you think. How climate, population density, disease prevalence, and agricultural history leave cognitive fingerprints.
The psychology of disagreement
Why smart people disagree, how we construct identity from our beliefs, and what happens to our brains when someone challenges our worldview.
The case for debate
Why disagreement is essential for both individual growth and democratic society — and how to disagree better by understanding the forces that shape the other side.
What people are saying
“Always fascinating but frequently mind-blowing”
“Provocative, wide-ranging and wonderfully written”
Read the science. Then see it in yourself.
Take the Opinion DNA assessment and map your own personality, values, and meta-thinking across 48 dimensions — the same dimensions explored in the book.
One-time purchase. Lifetime access. 30-day money-back guarantee.
Frequently asked questions
What is the connection between the book and Opinion DNA?
Opinion DNA grew out of the research behind the book. Turi Munthe spent years interviewing neuroscientists, psychologists, and philosophers about how beliefs form. Opinion DNA is the tool that lets you apply that research to yourself — mapping your own personality, values, and meta-thinking across 48 dimensions.
Do I need to read the book to take the assessment?
No. The assessment stands on its own. But reading the book will give you a much deeper understanding of why your scores look the way they do and what the science behind each dimension reveals.
Do I need to take the assessment to enjoy the book?
Not at all. The book is a standalone exploration of how human beliefs are formed. But taking your Opinion DNA assessment will make the book personal — you'll see your own mind reflected in the research.
Who is Turi Munthe?
Turi Munthe is the founder of Opinion DNA and the author of 'Why We Think What We Think', published by Penguin. He has spent years researching what shapes human opinion, working with over 60 experts from Oxford, Cambridge, NYU, and UPenn.
Where can I buy the book?
The book is available from Penguin, Amazon, and all major booksellers in hardcover, ebook, and audio formats.