Dennett, Daniel C.;
Penguin, 2004, 368 pages
ISBN 0142003840, 9780142003848
topics: | philosophy
Makes a case that freedom is a result of increasing complexity. Thus, higher-level structures (categories) were not present in ancient organisms, but have arisen as organisms have become more complex. One of the results is the emergence of free will, and Dennett argues that this free will can exist even in a deterministic world. While he does consider game theoretic notions of equilibrium, I am surprised that Dennett does not consider the complexities arising from nonlinear system behaviour, such as chaos, which implies that even though the system is deterministic, this is true only if the input is measured with infinite precision. Hence, since our sensory inputs are finite, things for most agents in the world are far from deterministic. Hence, in God's mind (with infinite precision) all our actions, including my typing this word here now, may be pre-determined, but for me it is an act of free will. The thrust of the argument is to support the case for humans being in some way distinct from other animals, and to tie in this argument with earlier positions in western philosophy linking human uniqueness with free will. As John Gray has pointed out in another review (below), this is ultimately an attempt to defend what is essentially a Judaeo-Christian stance: If natural selection had been discovered in India, China or Japan, it is hard to imagine it making much of a stir. Darwin's discovery signalled a major advance in human knowledge, but its cultural impact came from the fact that it was made in a milieu permeated by the Judaeo-Christian belief in human uniqueness. Gray argues that ideas don't propagate via memes alone, they also propagate by the sword. Making your opponents extinct may be a more successful approach than convincing them.
DETERMINISM is the thesis that "There is at any instant exactly one physically possible future." (van Inwagen 1983, p.3 An essay on free will, Oxford) p.25 Laplace's Demon: An intellect which at any given moment knew all the forces that animate Nature and the mutual positions of the beings that comprise it, if this intellect were vast enough to submit its data to analysis, could condense into a single formula the movement of the greatest bodies of the universe and that of the lightest atom: for such an intellect nothing would be uncertain; and the future just like the past would be present before its eyes. (Laplace 1814)
In this game, pixels are either turned on or off on a grid. The rules are strictly deterministic - some cells are turned on to start with, and then at each step, a cell dies if it has <2 or >3 neighbours. At the same time, an empty cell with exactly three live neighbours is turned on. [explore the game at http://serendip.brynmawr.edu/playground/life.html) Although the rules are deterministic, the overall effect is often described using a higher-level ontology than that of pixels. For example, the pattern on the left is a "glider", which replenishes cells and moves one step diagonally downwards every four iterations. glider beacon ; The "glider" is a type of "spaceship" which voyages across the universe of Life. Other configurations are "oscillators" (e.g. three cells in a row, flip 90 degrees each iteration, or the one shown above, a "beacon"). Other structures include "glider guns" which emit gliders periodically, "switch engines" etc. Here is a possible description: An eater can eat a glider in four generations. Whatever is being consumed, the basic process is the same. A bridge forms between the eater and its prey. In the next generation, the bridge region dies from overpopulation, taking a bite out of both eather and prey. The eater then repairs itself. The prey usually cannot. If the remainder of the prey dies out as with the glider the prey is consumed. (Poundstone 1985, p.38). Clearly the use of terms like "prey", "predator", "bridge reason", "repairs itself" attribute certain models of behaviour to these cell complexes, that were not part of the initial intent of the designers. These are typically known as emergent behaviours. Where did these behavioural abstractions come from? Are they real? At least most humans can immediately recognize them. Is there an information-theoretic basis due to which everyone (including other forms of intelligence) may agree that these phenomenon exist and are real? [NOTE: Coding theory - makes it more compact to talk thus of repetitive events.] [Note 2: The creatures that inhabit this space can be humongously complex. Certain patterns can be configured as logic gates; one can build a pattern that replicates an FSM - the system is an universal Turing machine. Another pattern, the Gemini, replicates itself in 34 million generations, and destroys the parent copy. ]
Plato speaks in the famous image of carving nature at its joints... literally, where one thing leaves off and the next thing starts - patterns that are salient and stable enough for us to identify. As we saw in the Life world, whereas the microscopic deterministic "physics" dictates every aspect of behaviour, it is natural to leap above the atomic level and describe the ... "connected hypersolids" ... that constitute macroscopic (not microscopic) regularities, and we use these to anchor our imagination when we think about causes and possibilities. 65 [possibly, these arise out of STATISTICAL REGULARITY - e.g. the MINIMUM ENTROPY PRINCIPLE, rather than any "natural to leap above" tendencies] We can describe such middle-sized patterns of atoms using the familiar system of informal predicates that apply to these entities, such as "has a length of 1 meter," "is red," "is human," and "believes that snow is white." - these informal predicates unleash a horde of problems concerning - vagueness - subjectivity - intentionality that fueled Quine's skepticism about possibility and necessity. [Quine created the DEMOCRITEAN universe - a set of point-atoms each specified by silver:(x,y,z,t), etc. to talk about possible worlds]. Proceeding gingerly, then, we may form sentences such as "There is something that is human." and determine if they apply to different possible worlds. 66 DETERMINISM: "There is at any instant exactly one physically possible future." - no two worlds start out exactly the same (if they did they would stay the same forever and be the same PW) - if any two worlds share the same state decription exactly, subsequently they all have the same state description. it is deterministic in only ONE direction - cannot tell the past. e.g. in Life, a 2x2 square can arise from 4x L-shapes, or the square itself. Problems: 1. we must know the laws of physics perfectly (a la Laplace's demon) 2. we must have perfect and complete knowledge of the state description - otherwise we will not be able to tell which of Vastly many microscopically different possible worlds in the set Phi is the actual world. COUNTERFACTUALS: 6. if Greenspan had sobbed in Congress, the market would have crashed. (if A then B) --> some set of worlds X, similar to our worlds, has the regularity that if A then C. thus the counterfactual can be interpreted as: 9. In the set of worlds X, A ==> C (70:9) How to choose the set X? It consists of worlds where A holds (or doesn't) as well as C (holds as well as doesn't)... it must be similar to actual world, so that the same laws hold, etc. CAUSATION: A sentence such as 6 is seen as making a claim more like: 10. Greenspan's sobbing caused the market to crash. (similar to p.71) Based on some factors: CAUSAL NECESSITY : Unless A happened, C would not have happened. If X includes those in which A, and not-A etc, and if all worlds in which C holds are also those in which A holds, then the statement may be causally necessary. CAUSAL SUFFICIENCY: We believe C to be the inevitable outcome of A; In any world where A occurs, C would ensue. THe agents cannot avert this consequent of their action.
from http://enjoyment.independent.co.uk/books/reviews/story.jsp?story=376373 If natural selection had been discovered in India, China or Japan, it is hard to imagine it making much of a stir. Darwin's discovery signalled a major advance in human knowledge, but its cultural impact came from the fact that it was made in a milieu permeated by the Judaeo-Christian belief in human uniqueness. If – along with hundreds of millions of Hindus and Buddhists – you have never believed that humans differ from everything else in the natural world in having an immortal soul, you will find it hard to get worked up by a theory that shows how much we have in common with other animals. Among us, in contrast, it has triggered savage and unending controversy. In the 19th century, the conflict was waged between Darwinists and Christians. Now, the controversy is played out between Darwinism and humanists, who seek to defend a revised version of Western ideas about the special nature of humans. The ringing tone of Dennett's declaration of human uniqueness provokes a certain suspicion regarding the scientific character of his argument. After all, the notion that humans are free in a way that other animals are not does not come from science. Its origins are in religion – above all, in Christianity.... In fact, despite all his impassioned protestations to the contrary, Dennett is seeking to salvage a view of humankind derived from Western religion. To be sure, he wants to demolish the metaphysical belief in freedom of the will that has been the foundation of this view in the past – but only in order to give it another, more solid foundation in contemporary science. Like many others over the past 100 years or so, Dennett looks to evolution for the moral uplift that used to be afforded by religion. In developing his conception of evolving freedom, Dennett relies heavily on Richard Dawkins' theory of memes: ideas that compete with one another in a way analogous to natural selection in biology. The trouble with this unhappy metaphor is that there is no known mechanism for the spread of ideas akin to the transmission of genes. The history of ideas is made largely by political power and human folly – not through the workings of natural selection. Dennett is vastly more sophisticated a thinker than Huxley [who viewed evolution as a form of progress, and evolutionary change as a form of good], but like him he seems to derive a curious comfort from the belief that human culture is an evolving process. Perhaps, like Huxley, he cannot help identifying himself with the evolutionary process and imagining that it is working obscurely to replicate his own values; but if there is such a thing as cultural evolution, it is no less blind, purposeless and value-free than biological evolution. Dennett describes human history as a "communal process of memetic engineering" – a saga that includes, he tells us, his own book. He seems not to have digested the fact that the world is full of memetic engineers who do not share his values, some of them using methods rather more effective than philosophical argument, and who are as much a part of cultural evolution as he is himself. [ John Gray is Professor of European Thought at the LSE]
Investigation of free will (and eventually for moral decisions / ethics) in a post-cartesian mechanistic world. If everything is deterministic, we don't have free will [ch.4]. So where does choice come from? Consider intelligence as a result of a number of autonomous processes (fantastic anecdote abt BSO temp conductor, who tried to make a point by inserting a false note on a music score, but the player played the correct note. When he appeared to hear the wrong note, and challenged the player, the riposte was: "I had played B-natural. Some idiot had written in a B-flat"). The point is that a number of autonomous processes acting together (he uses the game of Life, by Conway, to great effect p.36-41) create a nondeterminism where systems exhibit chaotic behaviours. Details Benjamin Libet's experiment on the onset of consciousness, who shows that certain brain patterns can reliably predict this conscious awareness - presents some of Libet's original figures (p.227-230). [The Volitional Brain: Towards a Neuroscience of Free Will by Benjamin Libet, Anthony Freeman, Keith Sutherland [books?id=GygmUh51_AcC]