Semantic information (Introduction)

by David Turell , Thursday, November 26, 2015, 00:40 (3069 days ago)

Skip the fist half of this discussion. It is a highly technical math approach to information. Find the subtitle for semantic information and look at that:-http://www.evolutionnews.org/2015/11/a_taxonomy_of_i101141.html-"The definition of semantic information is information that has meaning. As Dr. Randy Isaac explains, semantic information indicates "the significance of a message, whether or not an intelligent agent was involved.'" -***-"Well, where does meaning come from? We assign it. This is not what Shannon had in mind, and it's really not what's at stake with complex and specified information (CSI), as I'll explain below.-"CSI identifies some subset within a reference class of possibilities. Semantic information looks at subjective meaning. But CSI isn't about subjective meaning. It's objective.-"Dr. Isaac writes: "In abstract symbolism, the symbol has a meaning assigned to it which does not necessarily derive from its physical properties." I agree. Semantic information could occur by a natural cause, or by intelligence. For example:
• Human intelligence creates stop signs to tell car drivers to stop.
•Nature uses TGA in the genetic code to tell translation to stop. -***-"It's important to understand that the idea of complex and specified information is NOT an invention of ID proponents. The first use I'm aware of comes from origin-of-life theorist Leslie Orgel in the 1970s:-'[L]iving organisms are distinguished by their specified complexity. Crystals are usually taken as the prototypes of simple, well-specified structures, because they consist of a very large number of identical molecules packed together in a uniform way. Lumps of granite or random mixtures of polymers are examples of structures which are complex but not specified. The crystals fail to qualify as living because they lack complexity; the mixtures of polymers fail to qualify because they lack specificity.'"-(Leslie E. Orgel, The Origins of Life: Molecules and Natural Selection, p. 189 (Chapman & Hall: London, 1973).) -Comment: the author uses this to specify ways of looking for evidence of design, but the point is DNA carries useful information, which must be defined, and recognized that intelligence has to be involved to interpret the code.