Brain

The brain is an organ that evolved by the same processes as did fins, lungs, hearts, red blood cells, stripes on a land snail, DDT resistance in a fruit fly, or the parachute on a dandelion seed. The evolution of the brain is not fully understood (nor, for that matter, is that for a snail shell, the dandelion seed’s parachute, or the genetic mechanism by which fruit flies become DDT resistant), but many reasonable deductions can be made about its function and capabilities. Consciousness, thinking, reasoning – activities of the “mind” – are all centered in the brain and are phenomena as natural (and material) as the legs’ actions of standing, walking, running, and kicking. Seventeenth-century French philosopher Rene Descartes thought that was a divide between the material body and brain and the immaterial, nonphysical mind. His dualism that of seeing the mind as the “ghost in the machine” of the body, is so contrary to the view of most researchers today that neurologist Antonio Damasio titled his fine book on the brain ‘Descartes’ Error’. Scientists now assume that there cannot be thought without a brain and that thoughts are physical events with (often) physical consequences beyond the firing of nerve cells. For example, mental stress, such as that caused by the loss of a loved one, can depress the mental functioning of the immune system. There was a lot of truth in the old high school joke-question: “What’s the lightest thing in the world?” the answer was an erection, “because it takes only a thought to raise it.” If thoughts didn’t have a physical basis the required vasodilation couldn’t be triggered.

The physical nature of the mind is, of course, also demonstrated by the effects of accidental brain lesions, surgical destruction of parts of the brain to treat psychiatric disorders, the mind-altering hormones and therapeutic and recreational drugs. Many of the latter, remember, have been evolved by plants as defensive chemicals to alter the behavior of herbivores, specifically in response to the physical natures of the herbivores’ minds. ~ Page 120

The brain is conservative at the deep biochemical level like everything else, and at the cellular level too. . . . . The neuron is a standard eukaryotic cell with some exaggerations and really only one new idea. The evolution on the large-scale structures of the brain has again been fundamentally conservative, proceedings through modifications and additions. There is an old city, old places in the brain, which are vital. They were not superseded but modified, old and new often collaborating or working in parallel.

Since mammals appeared the most vigorous developments have been going on in one part of the suburbs so that our Greater Brain, the great hemispheres of the cerebrum occupy most of the skull. The cerebral cortex, more usually referred to simply as the cortex, is the convoluted outer shell of the hemispheres. As one might expect of a recent suburban sprawl, the newest part of the cortex -- the neocortex -- is in some ways less critically made than the deeper structures which is now largely conceals. For example there are significant differences in details of the folds of a cortex, between individuals and between the two hemispheres of an individuals. ~ Page 126 "Evolving Mind" - A.G.Cairns-smith

There is only brains, like that great city of molecules behind your eyes. It can make feelings, you know that. And if we believe it was a product of evolution through natural selection, and that it is a molecular mechanism like everything else in biology, then if we really knew all that molecules can do we should surely be able at least to outline the design of a feeling machine that was made of materials other than "the molecules of life". After all, these molecules were not selected in the first place with an eye to their future use as components of conscious mechanisms. They were molecules which some view early microscopic form of life happened to hit on, molecules which were suited to its requirements and which then became fixed in to provide the basis of all molecular engineering from then. Few new small molecules were even added to the basic types when it came to making brains -- a few modified amino acids as neurotransmitters, a fancy lipid here and there...

And then again at the level of the cell the machine that makes our conscious experiences was cobbled together out of only somewhat modified eukaryotic cells. All this does not speak of consciousness as a phenomenon that can only be created in one particular way.

So, yes, it should be possible to make a machine that feels, and almost certainly with other than 'biological' components.

Hands up who knows how. ~ Page 188 "Evolving Mind" - A.G.Cairns-smith

Unity of Experience. There is no unified "self" that generates internally consistent and seamlessly coherent beliefs devoid of conflict. Instead, we are a collection of distinct but interacting modules -- or neural networks -- that are often at odds with one another. According to the evolutionary psychologist Robert Kurzban, the brain evolved as a modular, multitasking, problem-solving organ -- a Swiss Army knife or practical tools, in the old metaphor, or an app-loaded iPhone, in Kurzban's upgrade. The module that leads us to crave sweet and fatty foods in the short term, for example, is in conflict with the module that monitors our body image and health in the long term. The module of cooperation is in conflict with the module fore for truth telling with the module for lying. Of course, because the brain does not sense itself opeating, we are blissfully unaware of all these networks running largely independently, so it feels as though there is unity of self. ~ Page 125 (Excerpt: "Heaven on Earth" ~ Author - Michael Shermer

. . . . Here is a truth that neuropsychology appears entirely to overlook: 'minds are not brains'. Please note that I do not intend anything non-materialistic by this remark; there are only brains, and minds are not some ethereal spiritual stuff a la Descartes. What I mean is that minds are the result of the social interaction between brains. As essentially social animals, humans are nodes in complex networks from which their mental lives derive most of their content. A single mind is, accordingly, the result of interaction between many brains, and this is not something that shows up on an fMRI scan. The historical, social, educational and philosophical dimensions of the constitution of individual character and sensibility are vastly more than the electrochemistry of brain matter by itself. Neuroscience is an exciting and fascinating endeavour which is teaching us a great deal about brains and the way some aspects of mind are instantiated in them, but by definition it cannot teach us everything, of what we would like to know about minds and mental life. ~ Page 121 Excerpt: :The Challenge of Things" - author - A.C.Grayling