Max Tegmark has a new paper Consciousness as a State of Matter. The paper is filled with mathematics which I am not going to try to explain or pretend to understand but there are parts of it which are fairly accessible to anyone with a modest understanding of modern science. Here is a good write-up of it without the mathematics. The paper takes the seemingly radical position that we can understand consciousness as another state of physical matter just like solids, liquids, and gases. I have argued in some other posts that consciousness must be material so I will find myself in agreement with the general sentiment even though I disagree with this approach There are, however, some additional aspects of this that Tegmark may be missing that I want to discuss.
Tegmark writes “the key difference between a solid, liquid, and a gas lies not in the types of atoms, but in their arrangement. In this paper, I conjecture that consciousness can be understood as yet another state of matter.”
Tegmark draws extensively on the work of Giulio Tononi and his Integrated Information Theory of consciousness. Tononi argues the consciousness consists of two features: information and integration. Both features must be present. A disc drive might contain a large amount of information but the information is not integrated. Every bit is either on or off independently from every other bit. For information to be integrated, the different bits need to interact with each other. The bits need to be clustered into complexes and networks that affect each other in a coordinated manner. The greater the amount of integration the greater the degree of consciousness. Tononi has a developed a theoretical, mathematical framework for measuring integration but has no practical way of measuring with human beings or other organisms.
Tegmark starts to build on this Tononi’s theory with an interesting chart which characterizes the states of matter he is considering. I reproduce this chart below:
|State of matter||Long-lived states?||Information integrated?||Easily writable?||Complex dynamics?|
Long-lived states means that the components maintain their arrangement for periods of time. In gases and liquids, the molecules are in constant movement and do not persist in a stable pattern. Information integrated is the integration that Tononi speaks about. Consciousness by Tononi’s theory is defined by integration of information. Tegmark leaves a question mark by computer suggesting that the computer state may be or could in the future be conscious. Memory may be described as a solid that can be easily read from and written to. Tegmark gives the example of a gold ring with an engraving. The engraving persists on the ring because it maintains long-lived states. If we wrote the engraving in water, it would quickly vanish. A computer not only has memory but also is dynamic. Think of a computer executing a simple program adding one to a variable in a loop. Not only is there memory to persist the value of the variable, the value is changing in a predictable fashion by the addition operation and a program that describes the logical steps. It is not static memory like the engraving.
Consciousness, the last state in the table, has all of these characteristics. Of course, just putting consciousness in a table with solids, liquids, and gases doesn’t mean that they really are in some way comparable or, more importantly, that it is useful in any to compare them. There is a big discontinuity between the first three entries in the table and the last three. We can transform solids into liquids and gases by adding energy. If I heat ice, it becomes water and eventually steam. Going the other way, if I remove energy from steam it cools to water and eventually ice. We can move from one state to another by changing the amount of energy. But how do we go from solid to memory? We can’t do it by removing energy. In fact, the recording of information requires energy. Computing requires even more energy and consciousness is very expensive. The human brain needs more energy than any other organ. We understand how to move between the first three states of matter but we do not know how to move from the first three to any of the last three or how to move between the last three.
Where is life in the states of matter and how does life itself differ from consciousness? Life has many long-lived states. Its hallmark is its persistence over time by copying its DNA. Its information is integrated into a unified whole – the organism itself. It is complex and dynamic. Its writability is shown every time a cell divides and writes a copy of its DNA. It constantly recreates itself by assimilating raw materials and energy from the environment It is dynamic. The entire notion of evolution is the changing information in life through natural selection.
Fundamentally Tegmark seem to have omitted the key transition point between solids and the only “states of matter” which most of us can agree possess consciousness. Even if we deny consciousness to any lower form of life than human, most of us agree that humans are conscious. Indeed, if we are not, then probably we must argue that consciousness itself does not really exist and, despite what most of us think and feel, we are really automatons. Despite the question mark in the column by computer, few of us would believe that computers are now conscious though we might debate whether they might become so in the future. Consciousness at this point in our experience in the universe is only a property of life. It came from life. It differs not a bit in Tegmark’s table from consciousness itself.
As I have argued extensively in this blog, consciousness is just an extension of life, not something radically different from it. It is a product of the evolving complexity of life and its increasing capacity to store information. In fact, I have gone one step farther to say that consciousness is built from the materials of life and that it is unlikely non-lifelike materials, such as computers as we know them, will even become conscious no matter how well they may be able to imitate human behavior or even exceed human intelligence.
In a new paper described as “A New Physics Theory of Life” Jeremy England tries to derive an understanding of life from the Second Law of Thermodynamics. Living beings in this view are dissipative engines that create entropy by assimilating energy from the environment and using it to reproduce. I quote from an article about it:
Self-replication (or reproduction, in biological terms), the process that drives the evolution of life on Earth, is one such mechanism by which a system might dissipate an increasing amount of energy over time. As England put it, “A great way of dissipating more is to make more copies of yourself.” In a September paper in the Journal of Chemical Physics, he reported the theoretical minimum amount of dissipation that can occur during the self-replication of RNA molecules and bacterial cells, and showed that it is very close to the actual amounts these systems dissipate when replicating. He also showed that RNA, the nucleic acid that many scientists believe served as the precursor to DNA-based life, is a particularly cheap building material. Once RNA arose, he argues, its “Darwinian takeover” was perhaps not surprising.
England’s concept is not exactly new. The idea that the Second Law of Thermodynamics is what life is about can be traced back to Erwin Schrodinger’s “What is Life?”. Others have built on this idea including Karo Michaelian and Eric D. Schneider with “Into the Cool”.
Coupled with the idea of life as an energy dissipating engine, however, must come an understanding about how “information manipulates the matter it is instantiated in” as Paul Davies puts it in the “The Algorithmic Origins of Life”. Life not only dissipates energy, it seems also to store and increase information. As the complexity of life increases, its capacity to store information increases. Energy and information are related. I quote myself from another post: “Consciousness is the encoding of information in near real-time just as life itself is the encoding of information in evolutionary time. Consciousness may also be a phase transition during which mind gains a qualitatively different level of control over the matter it is instantiated in from that of genetic and other regulatory information. This to me suggests that consciousness is an almost inevitable outcome of the evolution of living organisms”.
Ultimately Tegmark’s attempt to view consciousness as a state of matter falls apart because it misses the obvious connection between consciousness and life. The last three states of matter in Tegmark’s table, along with life itself, might be better considered “supra-states of matter” in that they are built on matter but go beyond them. These supra-states arise through the inherent self-organizing capability of life and its ability to convert energy into information, generating entropy in the process.