A Problem of Scale: Halfway in size between an atom and the universe

0bvious — Sun, 18 Feb 2007 16:10:04 -0800

"A human is halfway in size between an atom and the known universe"... This is a paraphrased quote I have come across several times. I like it. Who said it first? How true is it in the most literal sense? And, finally, what errors arrive in postulating a universe, or an atom, which can be measured AT ALL from our singular, relativistic, perspective? I found this quote from Cosmic Evolution which further complicates the whole relative size issue:

"Roughly halfway in size between an atom and a human, the amoeba has poor awareness and coordination. It generally responds only at the point stimulated, communicating the information sluggishly through the rest of its body. Although amoebas have developed a crude nervous system, living things that aspire to be more agile—and smarter—surely need quicker internal reactions." - link

Kind of sets another stage from which to view this question.

I also found this quote from Holmes Rolston which further complicates things:

"The human world stands about midway between the infinitesimal and the immense. The size of our planet is near the geometric mean of the size of the known universe and the size of the atom. The mass of a human being is the geometric mean of the mass of the earth and the mass of a proton. A person contains about 10²⁸ atoms, more atoms than there are stars in the universe. Such considerations yield perhaps only a relative location. Still, questions of place and proportion arise." - link

Who first made this often used statement? My earlier questions still stand :-)

Thanks...

Ask MetaFilter questions tagged with amoeba

A Problem of Scale: Halfway in size between an atom and the universe