CDS 011008-JLR CRSS
Chapter II: Sankhya Yoga
(Krishna speaking to Arjuna)
II.67. For the mind, which follows in the wake of the wandering
senses, carries away his discrimination, as the wind (carries
away) a boat on the waters.
COMMENTARY: The mind which constantly dwells on the sensual
objects and moves in company with the senses destroys altogether
the discrimination of the man. Just as the wind carries away a
boat from its course, so also the mind carries away the aspirant
from his spiritual path and turns him toward the objects of the
senses.
/////////////////////Did evolution come before life?
 08:00 15 September 2008
NewScientist.com news service
Bob Holmes
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A rudimentary form of natural selection likely existed in the primordial soup even before life arose on Earth. If so, the complex "ecosystem" of prebiotic molecules may have made the eventual arrival of life much more probable.
Most experts presume that life arose from complex molecules such as nucleic acids and proteins, which were assembled from a mix of simpler units strung together with chemical bonds.
To examine how this might occur, Martin Nowak and Hisashi Ohtsuki, mathematical biologists at Harvard University, used simple equations to model the growth of such chains of building-blocks.
The model shows that because longer chains require more assembly reactions, they should be much less common than short chains. And if some assembly reactions run faster than others, then chains built from these fast-assembling sequences of building blocks grow to be most abundant.
Threshold of life
This bare-bones equivalent of natural selection makes the prebiotic soup an interesting place, they say.
"It generates a rich evolutionary dynamic – or what I would want to call a 'prevolutionary' dynamic – where you have diversity, you have information, you have complicated chemistry," says Nowak.
Such a system, full of novel, interacting molecules, would be the ideal milieu to generate a molecule with attributes that would favour the assembly of copies of itself. Nowak's prebiotic selection could then act to refine this ability by ensuring that better replicators become more common.
At some point, Nowak's model predicts, the best replicator may get fast and accurate enough to dominate the population, sucking up all the resources and driving all the other prebiotic sequences extinct. This is the threshold of life.
"Ultimately, life destroys pre-life," says Nowak. "It eats away the scaffold that has built it."
'Murky area'
In showing that selection actually precedes the origin of life, and helps to shape it, Nowak helps bridge the gap between nonliving and living systems. In a sense, he says, the prebiotic soup is constantly testing possible replicators, making it much more probable that one might eventually reach the threshold of life.
Nowak's model helps clarify a murky area of research on prebiotic mixtures, but it offers little direct guidance to experimentalists, says Irene Chen, an origin-of-life researcher also at Harvard.
"The tricky part is figuring out exactly what the relevant chemicals to use are," she says. "Martin's model is basically agnostic about that question."
Journal reference: Proceedings of the National Academy of Sciences (DOI: 10.1073/pnas.0806714105)
//////////////////////////////////////////Pack in More of the Three F’s
Fun, Fulfilment, and Freedom – what I call the Three F's - embody a whole lot of what people are looking for in life. Here are some quick definitions,
Fun, n. - A source of enjoyment or pleasure; playful activity.
Ful-fill'ment, n. - To bring into actuality; to complete; a feeling of satisfaction at having achieved your desires.
Free-dom, n. - The capacity to exercise choice, free will; frankness or boldness; the absence of constraint in choice or action.
/////////////////////////////The secret of getting started is breaking your complex, overwhelming tasks into small manageable tasks, and then starting on the first one.
Posted: 23 Sep 2008 09:00 AM CDT
~ Mark Twain
///////////////////////////////My philosophy? Simplicity plus variety.
~Hank Stram~
POSTED BY bobby maz AT 10/01/2008 5:49 AM
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