MOTION MOUNTAIN

the story of the brain 237
Ref. 206
Vol. I, page 27
Challenge 243 s
Page 299
Challenge 244 e
During childhood, everybody is a physicist. When we follow our own memories backwardsintimeasfaraswecan,
wereachacertainstage,situatedbeforebirth,whichforms
thestartingpointofhumanexperience.Inthatmagicmoment,wesensedsomehowthat
apart from ourselves, there is something else. The first observation we make about the
world, during the time in the womb, is thus the recognition that we can distinguish two
parts: ourselves and the rest of the world. This distinction is an example – perhaps the
first – of a large number of ‘laws’ of nature that we stumble upon in our lifetime. Being
a physicist started back then. And it continued. By discovering more and moredistinctions
we bring structure in the chaos of experience. We quickly find out that the world
is made of related parts, such as mama, papa, milk, earth, toys, etc. We divide the parts
in objects and images.
Later, when we learn to speak, we enjoy using more difficult words and we call the surroundingstheenvironment.
Dependingonthecontext,wecallthewholeformedbyoneself
and the environment together the (physical) world, the (physical) universe, nature,
or thecosmos. These concepts are not distinguished from each other in this walk;* they
are all taken to designate the sum of all parts and their relations. They are simply taken
here to designate thewhole.
The discovery of the first distinction in nature starts a chain of similar discoveries that
continue throughout our life. We extract the numerous distinctions that are possible in
the environment, in our own body and in the various types of interactions between them.
The ability to distinguish is the central ability that allows us to change our view from that
of the world aschaos, i.e., as a big mess, to that of the world as asystem, i.e., a structured
set, in which parts are related in specific ways. (If you like precision, you may ponder
whether the two choices of ‘chaos’ and ‘system’ are the only possible ones.)
In particular, the observation of the differences between oneself and the environment
goes hand in hand with the recognition that not only are we not independent of the
environment, but we are firmly tied to it in various inescapable ways: we can fall, get
hurt, feel warm, cold, etc. Such relations are called interactions. Interactions express the
observation that even though the parts of nature can be distinguished, they cannot be
isolated. In other words, interactions describe the difference between the whole and the
sum of its parts. No part can be defined without its relation to its environment. (Do you
agree?)
Interactions are not arbitrary; just take touch, smell or sight as examples.They differ
in reach, strength and consequences. We call the characteristic aspects of interactions
patterns of nature, or properties of nature, or rules of nature or, equivalently, with their
historical but unfortunate name, ‘laws’ of nature. The term ‘law’ stresses their general
validity; unfortunately, it also implies design, aim, coercion and punishment for infringement.However,
no design, aim or coercion is implied in the properties of nature, nor is
infringement possible. The ambiguous term ‘law of nature’ was made popular by René
Descartes (b. 1596 La Haye en Touraine, d. 1650 Stockholm) and has been adopted enthusiasticallybecauseitgave
weight to the laws of the state – which were far from perfect
* The differences in their usage can be deduced from their linguistic origins. ‘World’ is derived from old
Germanic ‘wer’ – person – and ‘ald’ – old – and originally means ‘lifetime’. ‘Universe’ is from the Latin,
anddesignatestheone– ‘unum’ –whichoneseesturning – ‘vertere’,andreferstothestarredskyatnight
whichturnsaroundthepolarstar. ‘Nature’ comesalsofromtheLatin,andmeans ‘whatisborn’. ‘Cosmos’
isfromGreekκόσµος andoriginally means ‘order’.
Motion Mountain – The Adventure of Physics copyright © Christoph Schiller June 1990–November 2015 free pdf file available at www.motionmountain.net