"How mind is related to matter" is an ancient philosophical question which is becoming a core question in science as well, with ramifications in Physics, Psychology, Biology, Mathematics, Computer Science, Neurophysiology, etc.

I believe that new insight in mind, cognition and consciousness will come from a revision of science. At every point in the history of science, a paradigm shift allows to explain previously unexplained phenomena. Modern science has introduced and is introducing a number of "paradigm shifts" that are changing our perception of the universe and of who we are. Namely:

• Herb Simon's symbolic processing paradigm
• Jerry Fodor's computational functionalism
• Kenneth Craik's representational paradigm
• Charles Darwin's theory of evolution
• Albert Einstein's theory of relativity
• Ilya Prigogine's thermodynamics of non-equilibrium systems
• Gerard Edelman's theory of neural selection
• Fredrick Bartlett's reconstructive memory
• William James' connectionism
• James Gibson' ecological realism
• Noam Chomsky's generative grammar
• Stuart Kaufman's self-organization
• Humberto Maturana's autopoiesis
• George Lakoff's cognitive metaphor
• Roger Penrose's quantum theory of consciousness
• Lotfi Zadeh's fuzzy logic
• Rodolfo Llina's brain model
• Allan Hobson's theory of dreaming

I believe that these and other paradigm shifts will allow us to achieve a better understanding of what "thought" is, how it related to the matter of the brain and matter in general, and why we think at all.

Interest on the subjects of mind, consciousness and life is growing exponentially and is affecting a growing number of disciplines. What used to be the exclusive domain of philosophical speculation is now part of scientific research conducted by neurophysiologists, biologists, physicists, mathematicians, computer scientists and cognitive psychologists. All of a sudden new fascinating horizons have been opened for science. A variety of new disciplines have established themselves: Artificial Intelligence, Artificial Life, Cognitive Science, Systems Theory, Self-organizing Systems, etc. Even more important, a new vision of the world we inhabit has begun to materialize, one in which order is spontaneous, one in which the properties of life and intelligence "emerge" from matter, from energy and from a few fundamental laws. For the first time ever, it seems possible to reconcile mind and matter, to unify in one powerful theory both Physics and Psychology.

This is one of the most exciting fields of study of our days. It deals with the philosophical debate on the relationship between mind and matter, with neurophysiological models of the brain and computational theories of cognition. It requires integrating models of memory, reasoning, learning, emotions, common sense, language, metaphor, and even dreams from different perspectives (psychological, biological, computational). It is a fascinating journey around the world of the scientific ideas that are likely to shape the intellectual scenario of the third millennium.

Physics has explained everything we have found in the universe. We know how the universe started and how it will end. We know what drives it. We know what makes it. Our knowledge of fundamental forces and elementary particles is increasing daily. Two things remain to be explained: how am I alive and how do I think. What does it take for something to be alive and to think? Can we "build" a machine that thinks and is alive? What is thought (consciousness)? And what is life? Physics has no answer. It never tried to give an answer. Life and thought were "obviously" beyond the reach of formulas. Well, maybe the formulas are wrong. Or maybe religious convictions kept scientists from viewing living and thinking as physical phenomena to be studied the same way we study galaxies and electricity. The most important revolution of our century may be the idea that thinking and living can (and must) be explained by Science, just like any other phenomena in the universe. Science may never be the same again, literally. Any scientific theory that does not provide a credible account for consciousness and life is faulted from the beginning, as it ignores the two phenomena its own existence depends upon. We are alive and we are conscious.

The final step of the scientific program that started thousands of years ago, when humans first started asking themselves questions about the universe, will then be to find out the meaning of all this: why are we conscious and why are we alive? why is the universe the way it is and why are we in it? Meaning has become the ultimate goal of science. As much as we think we know, we still don't know much: we don't even know why we know what we know.

A new view of nature is emerging, which encompasses both galaxies and neurons, gravitation and life, molecules and emotions. As a culmination of centuries of studying nature, mankind has been approaching the thorniest subject of all: ourselves. We are part of nature, but science leaves us in the background, limiting our role to the one of observers.

For a long time we have enjoyed this privileged status. But we seem no longer capable of eluding the fundamental issue: that what we have been studying for all these centuries is but us, albeit disguised under theories of the universe and theories of elementary particles. And now it is about time that we focus on the real subject. The mind appears to us as the ultimate and most refined product of life. And life appears to us as the ultimate and most refined product of matter. Life and mind must follow from a logical inference on the essence of the universe. If we had the right theory of the universe, we would need no effort in explaining why life happened and what the mind is.

The fact that we do not have yet a good theory of the mind means that probably we do not have a good theory of the universe. Therefore, in a sense, the new science of the mind is doing more than just studying the mind: it is indirectly reformulating the program of Science in general.

Thanks to progress in all fields, from Mathematics to Neurobiology, our knowledge has been immensely enriched by a wealth of empirical data and by a wealth of theoretical tools. While differing on the specifics, many scientists and philosophers feel that mankind is now ready for a momentous synthesis. The main theme of such a synthesis may be that of the spontaneous "emergence" in our universe of such unlikely properties as life and consciousness. If we can explain how it developed, we can explain what it is and how it works. And what it means.

And what we are.

Ultimately, my research is about the gap between "I" and "me".

I believe in the existence of a common underlying principle that governs inanimate matter (the one studied by Physics), living matter and consciousness. And I believe that principle to be a form of Darwinian evolution.

The second underlying principle of my research is "ex nihilo nihil fit": nothing comes from nothing. Life does not arise by magic: it must come from properties of matter. Ditto for cognition. Ditto for consciousness. Many schemes have been proposed to explain how life or consciousness may be "created" from inanimate and unconscious matter, how a completely new property can arise from other properties. I don't believe this is the case. Both life and consciousness are ultimately natural phenomena which originate from other natural phenomena, just like television programs and the motion of stars.

The term "mind" has been abused so much that I have become hostile to it. The terms that I accept are "brain" and "consciousness". The brain is made of neural assemblies and consciousness is made of what we call (for lack of a better term) "thoughts". Neural assemblies are interconnected neurons and thoughts are made of interconnected emotions. The dynamics of both systems is controlled by a law of selection: neural assemblies and thoughts are continuously generated and experience determines which ones get stronger and which ones get weaker.

The substance of the brain and the substance of consciousness are the same. Brain processes and thoughts arise from different properties of the same matter, just like a piece of matter exhibits both gravitational and electric features. The feature that gives rise to consciousness is therefore present in every particle of the universe, just like the features that give rise to electricity and gravity.

What we call "mind" is actually two things, which must be carefully kept separate: "cognition" (i.e., the faculties of remembering, learning, reasoning, etc.) and consciousness. Cognitive faculties do not require consciousness. Cognition and consciousness are related only because we have not explained them yet. Cognition is a feature of all matter, whether living or not: degrees of remembering, learning, etc. are ubiquitous in all natural systems. They can be explained without revolutionizing Science. The "emotions" associated with them belong instead to consciousness, just like the emotions of tasting or pleasure. The explanation of consciousness does require a conceptual revolution in Science, specifically the introduction of a new feature of matter, which must be present even in the most fundamental building blocks of the universe.

Biology and Physics offer us completely different theories of Nature. Physics' view is "reductionist": the universe is made of galaxies, which are made of stars which are made of particles. By studying the forces that operate on particles, one can understand the universe. Biology's view is Darwinist: systems evolve. Consciousness, like all living phenomena, can be more easily explained in the framework of Biology than in the framework of Physics.

Reconciling the two views is the great scientific challenge of the next century.

We know that the world of living beings is a Darwinian system: competition, survival of the fittest, evolution and all that stuff. We know that the immune system is a Darwinian system. We are learning that the brain is also a Darwinian system, where the principles of natural selection apply to neural connections. It is intuitive that memory is a Darwinian system: we remember the things that we use frequently, we forget things we never use. I claim that the mind is a Darwinian system as well: competition, survival of the fittest and evolution work among thoughts as well. The Darwinian system recurs at different levels of organization, and one of them happens to be our thought system, i.e. our mind.

I also believe that the solution to the mystery of consciousness lies in a fundamental flaw of Physics. The two great theories of the universe that we have today, Quantum Physics and Relativity Theory, are incompatible. They both have an impressive record of achievements, but they are incompatible. One or both must go. I believe that once we replace them with a theory that is equally successful in explaining the universe, consciousness will be revealed to be a trivial consequence of the nature of the world.

Summarizing, my research deals with these recurring themes:

• The mystery of life can be explained by science and it is being explained as a property of matter, no less than electricity or evaporation
• Mind in the sense of "cognition" could be explained by science but science has been trapped in vague and unscientific definitions of "mind", "intelligence", "thought"
• Once "mind" is restricted to "cognition" (memory, learning, reasoning, etc.), it will be reduced to another property of matter, actually ubiquitous in nature
• Consciousness is the real mystery, still unexplained, and the cause may very well lie in a fundamental inadequacy of our science, a fundamental limit in our Science to explain natural phenomena
• A new science, which could accommodate a theory of consciousness, may be born out of the many paradigm shifts that have been introduced in several scientific disciplines over the last century. This would be a truly interdisciplinary science.