Wednesday, July 28, 2010

The critical reductionist

[W]e may be faced with the possibility that the origin of life (like the origin of the universe) becomes an impenetrable barrier to science, and a residue to all attempts to reduce biology to chemistry and physics. For even though Monod's suggestion of the uniqueness of life's origin is refutable --by attempts at reduction, to be sure-- it would amount, if true, to a denial of any successful reduction. With this suggestion Monod, who is a reductionist for reasons of method, arrives at the position which, I believe, is the one forced upon us all in the light of our earlier discussion of the reduction of chemistry to physics. It is the position of a critical reductionist who continues with attempted reductions even if he despairs of any ultimate success.Yet it is in going forward with attempted reductions, as Monod stresses elsewhere in his book, rather than in any replacement of reductionist methods by 'holistic ones', that our main hope lies --our hope of learning more about old problems, and of discovering new problems which, in turn, may lead to new solutions, to new discoveries.
Karl Poppper, The Open Universe, Scientific reduction and the essential incompleteness of all science.

Tuesday, July 27, 2010

Randomness cannot be defined

"Borel's conclusion is that there can be no one definitive definition of randomness. You can't define an all-inclusive notion of randomness. Randomness is a slippery concept, there's something paradoxical about it, it's hard to grasp. It's all a matter of deciding how much we want to demand. You have to decide on a cut-off, you have to say «enough,» let's take that to be random."
Gregory Chaitin, Meta Math!, Complexity, randomness and incompleteness.

Wednesday, July 21, 2010

Rooms for letters

"Writing, a cultural tool, has evolved to make use of the inferotemporal neurons'preference for certain shapes. «Letter shape,», Dehaene writes, «is not an arbitrary cultural choice. The brain constrains the design of an efficient writing system so severely that there is little room for cultural relativism. Our primate brain only accepts a limited set of written shapes."
Oliver Sacks, in A Man of letters, The New Yorker, June 28, 2010.

Sunday, July 11, 2010

A naked, sweating animal

"Actually, Dr. Bramble was surprised to find that all runnning mammals are restricted to the same cycle of take-a-step, take-a-breath. In the entire world, he and David could only find one exception:
You.
«When quadrupeds run, they get stuck in a one-breath-per-locomotion cycle,» Dr. Bramble said. «But the human runners we tested never went one to one. They could pick from a number of different ratios, and generally, preferred two to one.» The reason we're free to pant to our heart's content is the same reason you need a shower on a summer day; we're the only mammals that shed most of our heat by sweating. All the pelt-covered creatures in the world cool off primarily by breathing, which locks their entire heat-regulating system to their lungs. But humans, with our millions of sweat glans, are the best air-cooled engine that evolution has ever put on the market.
«That's the benefit of being a naked, sweating animal,» David Carrier explains. «As long as we keep sweating, we can keep going.»
Christopher McDougall, Born to run, Chapter 28.