Notes toward a new foundation of knowledge
2016, May 23
Biotechnology. Recent advances in sequencing and editing genomes make it now possible to wrest from nature the future of human evolution. This awesome power makes the question what ought to be done central. However, science and technology can only provide information about what can be done, but not about what ought to be done. Addressing the question what ought to be done is within the domain of philosophy, specifically the subfield of ethics. The basic tenets of ethics are an empirical issue: Are there innate commonalities of human nature? Can choices made affect behavior? In conclusion, at present there is no empirically based conceptual frame-work with which to address the vital most issues confronting humanity this century. The time has come to bring the foundation of knowledge up to date. It may prove to be a survival imperative.
Innateness. Brain prosthetics for the born deaf elicit sensations of sound by the direct electrical stimulation of hearing-related brain loci. This proves that the sensation of sound is innate and evoked by the brain. The same is true of all sensations. Hence, our experience of the world is phenomenal. Our knowledge of the physical is inferred from the phenomenal. This consequence brings to an end the three hundred year-old legacy of the tabula rasa doctrine (Locke 1690; Hume 1777).
Mental causation. Brain loci that are activated when a voluntary movement is made are also activated when such a movement is imagined. This fact is the basis for providing persons paralyzed from the neck down with brain computer interface (BCI) to control with their thoughts things like moving the location of a cursor on a computer screen or the action of a mechanical wheelchair. Thus, it is commonplace for the non-physical mind to affect the brain. These facts show that the assumption that only physical causes can have physical effects is false, and consequently that physics is a profoundly incomplete description of nature.
Human nature and conduct. The innate commonalities that underlie the apparent diversity of human cultures constitute human nature. Human nature is the empirical grounds for human conduct. The tabula rasa doctrine denies that any mental faculty is innate. It contributed to the fact that ethical and legal systems of the West are non-universal. Such systems are inherently ineffective in addressing long-term global issues. In due course ethical and legal systems will be put on firmer empirical grounds – the earlier the better.
Whatever is true of all cell types of the body is necessarily true of brain cells
2016 May 24
The cell is the basic unit of function. To the first approximation the cell-types of an organism contain the same genome. What distinguishes one cell-type from another are the proteins that can be, or are expressed in it. The protein-specificity of the cell is the primary determinant of its phenotype and intrinsic function. Whatever is true for all cell-types of the body is necessarily true for brain cells.
The discovery of the structure of DNA and cell-type- specificity. Ever since Theodor Schwann identified the cell as the basic unit of function, without proving the mechanism of action. The discovery of the structure of DNA in 1953 shed light on how the molecular constitution of the cell determines its phenotype and intrinsic function. There are no empirical studies indicating the need to downplay the central role of cells in biological function.
Three fields where the cell does not play central role
Genetics. In genetics, a gene is identified by its location on a particular chromosome and its expression in a particular organism. In some cases, the parts of the organism in which it is expressed are also noted. What is typically excluded is cell-type membership of the gene product (e.g. protein). There have been numerous genome-wide association studies (GWASs). The hope for major medical advances did not materialize. This should have been expected; you cannot be cell-blind and get anywhere in biology.
Action potentials and cellular communication. One misconception about the brain function are consequences of the mistaken assumption that in a chemical synapse action potentials cross the synaptic gap and bind to post-synaptic receptors. That mistake was first made by Warren McCulloch and Walter Pitts in 1943 when they used this empirically false assumption to claim to have proven that the brain is a universal Turing machine (UTM), and later in 1949 by Donald O. Hebb to explain neural function by excluding the contribution cells to their own output. This is the primary reason why to date, attempts to account for neural function have failed. Since protein-specificity of the cell is the primary determinant of its function, the first thing that needs to be done is to determine protein-specificity of brain cells. This has not yet been done. And, there is no technical difficulty in doing so, proving that the present trends are misdirected.
The Hebbian synapse. Donald Hebb accepted the view of his mentor, Karl Lashley, that cells and brain loci do not have specificity of function. He therefore proposed that the specificity is obtained by the interconnection of the local cellular network where the synapses are modified by experience. It is indeed factual that synapses are modified by experience. Such modifications are downstream events of what happens within cells. The Hebbian view shifted intracellular intrinsic function of the cell into the synapses. Neuroscientists therefore seek functional clues in the neural code. Thus far, they have failed. The reason is simple, neural function is not in the neural code.
The computer of the brain.
The function of proteins is structure-dependent. A protein is a linear (1D) sequence of amino acids. However, the function of a protein is determined by its native three-dimensional (3D) structure. The 1D structure does not determine its 3D structure. Furthermore, the genome does not contain information about protein folding. It is laws of nature that determine protein folding. How laws of nature determine protein folding is not known. Hence, the aspiration to model cellular function computationally is not presently realizable.
Structure-independent function. In biochemistry, structure determines function: a function may be understood as a change of structure over time. Observing physical events involve measurements. The mathematical description of measured quantities is analog. Such description may involve digital events. Consider, in contrast the digital switch. It can be made one of numerous materials, and it can operate on one of several different principles, such as mechanical, chemical magnetic, or electrical. Furthermore, considerations of speed, energy consumption, and error-rate are, in principle, not relevant. The binary digital switch performs a logical operation stripped from physical attributes. The general-purpose digital computer can viewed as an ensemble of digital switches.
The Universal Turing Machine (UTM). Alan Turing (1936, 1937) undertook to explicate the notion of computation. Turing described a simple abstract computer (now called the Universal Turing Machine) that could compute anything that other computers could compute, proving that the algorithm that specify a given computation is independent of the mode of it computation. It is generally overlooked that not only the UTM function is structure-independent, but that it is largely made independent of law of nature, such as an unlimited energy for operation, unlimited memory, and the impossibility of making errors.
Physicalism and Artificial Intelligence. Physicalism postulates that only the physical brain matters, leading to the quaint conclusion that consciousness is an evolutionary fluke. Artificial Intelligence (AI) goes ways further. Contrary to evidence, it postulates that the brain is a biological Universal Turing Machine, implying that computations performed by brains can also be performed by non-biological computers. In sum, Physicalism declares the mind superfluous, while Artificial Intelligence find that so is also the brain. It is time to review and revise basic assumptions.
Quote of the Week
How is it that anything so remarkable as a state of consciousness comes about as a result of irritating nervous tissue, is just unaccountable as the appearance od Djin when Aladdin rubbed his lamp.