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  • Hardcover $30.00

    Aug 07, 2012 | 384 Pages

  • Ebook $5.99

    Aug 07, 2012 | 380 Pages

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“Both playful and philosophical, this extravagant book addresses questions about the root of consciousness in a unique way…The book is a visual delight as well as an impressive read, its lavish artwork and literary references demonstrating just how fully complementary art and science can be.”
Publishers Weekly, starred review

“Giulio Tononi is a man of bold and original mind who has developed a fundamental new theory of consciousness. In Phi, he calls on all the resources of drama, metaphor, and the visual arts to present his scientific insights, in the form of imaginary dialogues in which Galileo meets Francis Crick, Alan Turing, and other major thinkers of the twentieth century. This is an astonishing (and risky) literary device, but Tononi pulls it off triumphantly. He makes the deepest neuroscientific insights come alive.”
—Oliver Sacks, author of Musicophilia
“You may or may not endorse Giulio Tononi’s views on how the brain generates consciousness, but you can certainly agree that his book is a garden of intellectual delights.”
—Antonio Damasio, author of Self Comes to Mind and Descartes’ Error
“This wonderful book reads like a popcorn novel but informs like a primer on consciousness and where it comes from. By turns exciting, challenging, and thought provoking, Giulio Tononi’s marvelous imagination explores the origin of thought, sensation, and feeling. Learning about the difference between the cerebrum and the cerebellum doesn’t sound like fun, but here you encounter them amidst fat friars shouting in vulgar Latin, nymphs of radiant beauty, and a mysterious juggler on a unicycle. I’ve always taken pride in being a conscious, sentient being; after reading Phi, I’m beginning to understand what it means when I say that!”
—Leonard Mlodinow, author of Subliminal

“An original, provocative tale of a scientist’s quest to understand how the brain generates consciousness…A challenging, rewarding read that will undoubtedly alter your consciousness.” –Kirkus  

“Charming.” –CultureLab   
“Tononi has pushed the study of consciousness forward…the book is lavishly illustrated with paintings and scientific images, poetically written, and unashamedly speculative, weighing some of the ‘meaning of life’ questions Tononi has been thinking about during his long career as a consciousness researcher. It’s a fascinating celebration of the complexity of the brain and mind.” –Boston Globe   

Table Of Contents


1 The Dream of Galileo
Part I: EVIDENCE: Experiments of Nature
2 Introduction
3 Cerebrum
In which is shown that the corticothalamic system generates consciousness
4 Cerebellum
In which is shown that the cerebellum, while having more neurons than the cerebrum, does not generate consciousness
5 Two Blind Painters
In which is shown that sensory inputs and pathways are not necessary for consciousness
6 A Brain Locked In
In which is shown that motor outputs and pathways are not necessary for consciousness, nor are they sufficient
7 Empress Without Memory
In which is shown that many brain circuits that help us see, hear, remember, speak, and act are not necessary for consciousness
8 A Brain Split
In which is shown that consciousness is divided if the brain is split
9 A Brain Conflicted
In which is said that consciousness can split if different regions of the brain refuse to talk to each other
10 A Brain Possessed
In which is shown that when cortical neurons fire strongly and synchronously, as during certain seizures, consciousness fades
11 A Brain Asleep
In which is shown that when cortical neurons can be on and off only together, as during dreamless sleep, consciousness fades
Part II: THEORY: Experiments of Thought
12 Introduction
The Enigma of Consciousness
13 Galileo and the Photodiode
In which is shown that the humble photodiode can tell light from dark as well as Galileo
14 Information: The Manifold Repertoire
In which is shown that the repertoire of possible experiences is as large as one can imagine
15 Galileo and the Camera
In which is shown that the sensor of a digital camera has a large repertoire of possible states, perhaps larger than Galileo’s
16 Integrated Information: The Many and the One
In which is shown that consciousness lives where information is integrated by a single entity above and beyond its parts
17 Galileo and the Bat
In which is feared that the quality of experience cannot be derived from matter
18 Seeing Dark (Deconstructing Darkness)
In which is said that darkness does not exist in a void but requires a context
19 The Meaning of Dark (Constructing Darkness)
In which is shown that darkness is built of many nested mechanisms that specify what it is not
20 The Palace of Light
In which is shown that an experience is a shape made of integrated information
21 The Garden of Qualia
In which is said that the universe is mostly dark, but the largest stars are closer than one thinks, if they are looked at with the proper instrument
Part III: IMPLICATIONS: A Universe of Consciousness
22 Introduction
Sparks and Flames
23 Nightfall I: Death
In which is said that, if consciousness is integrated information, it dissolves with death
24 Nightfall II: Dementia
In which is said that consciousness disintegrates with dementia
25 Nightfall III: Dolor
In which is said that, if the quality of consciousness is a shape made of integrated information, it can be turned into the only real and eternal Hell
26 Twilight I: Consciousness Diminished
In which is said that consciousness can be present in the absence of language and reflection
27 Twilight II: Consciousness Evolving
In which is said that animals are conscious, too
28 Twilight III: Consciousness Developing
In which is said that consciousness must be present, to some degree, even before birth
29 Daylight I: Consciousness Exploring
In which is said that, by investigating nature, new qualia are discovered
30 Daylight II: Consciousness Imagining
In which is said that art and imagination invent new shapes within the mind
31 Daylight III: Consciousness Growing
In which is said that, by growing consciousness, the universe comes more into being, the synthesis of one and many
32 Epilogue
Three Late Dreams
33 Afterthoughts
Study Questions
Illustration Credits

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