Knowledge, belief & agnosticism (Agnosticism)

by David Turell , Saturday, March 08, 2008, 19:55 (6104 days ago) @ clayto

clayto writes: "1. It looks to me quite likely that when the conditions for life are present then often (not necessarily always) life develops, just as for example when the conditions for fire are present a flame develops
 
 2. Why should this not be so?" The conditions for oxidation in a fire are easy to create on earth from inorganic and organic matter. Life is very difficult to create from inorganic and organic matter. Yet clayto is correct. The Theory is that Earth cooled enough after formation to allow life about 4 billion years ago (bya). Accepted evidence of life appeared 3.6 bya, and may have appeared 3.8 bya. For some reason life wants to pop up on Earth, seemingly against all odds as shown by the origin of life scientists and their failures. 
 
 "3. We now know that on this planet the conditions for life are much more varied and range between much greater extremes than was previously thought, though we do not yet have evidence for other planets"
 
 "4. I suspect (I do so wish I knew!) that life is a a natural and widespread phenomenon throughout the universe, arising where the widely varied conditions are found and that there is nothing particularly mysterious or 'unique' about it" This is Fred Hoyle's Panspermia theory, and it may be true that life has arisin elsewhere. We have no way of knowing that life is'natural and widespread', only that it seems to have appeared here on Earth in many extreme forms rather quickly and easily.
 
" 5. It seems to me that what would be mysterious is if did turn out that life is uncommon, even 'unique' and not 'natural' in much the same way that fire is natural" I agree that life on Earth uniquely would be a mystery to be carefully considered. A book that takes this viewpoint is "Rare Earth, Why Complex Life is Uncommon in the Universe", by Ward and Brownlee, 2000. It points out the unique circumstances on Earth that allow life. 
 
 "6. Once we have life / reproducibility in any form I can see no reason why its development should not be virtually limitless"
 
 "7. Why should this not be so?" It requires an information-rich DNA/RNA coding system. Life an Earth has that coding system, which doesn't just make proteins, ala Watson and Crick; It directs them in the formation of new individuals, with a construction sequence just like the sequence used in building a building. For example, the electricians can't run wires if the walls are completed first. In a fetus the arteries, veins, lymphatics and nerves have to be directed to their proper places of origin and destination. Not like starting a fire.