[extropy-chat] Gravity was qualia bet

[Diego Caleiro]

Actually, what we call matter is a given set of properties, and there is no 
possible philosophical evidence that there is any "substantial, essential" 
thing that must "have" this properties....


Just like "I think there fore I am"   is wrong because it pressuposes that a 
thought must have a thinker,   thinking of gravity as a non phisical property 
is wrong because we don't know, and never will know if there is indeed a 
"substantial, essential" thing that has phisical properties. Or if "matter" 
is only an intuitive intentionality we have atributted to the properties we 
see in the world.  

There is no way to say that there is a matter to have the properties we see, 
only to say that the properties are there. Gravity is there also, so it is 
not different significantly ( in a dualist sense) from matter.  Gravity does 
not pressupose mysticism. 


Hence Newton arrived at the view that the planets are attracted to the sun by 
a force, which is called gravitation. This whole point of view, as we have 
seen, is superseded by relativity. There are no longer such things as 
'straight lines' in the old geometrical sense. There are 'straightest lines', 
or geodesies, but these involve time as well as space. A light-ray passing 
through the solar system does not describe the same orbit as a comet, from a 
geometrical point of view; nevertheless each moves in a geodesic. The whole 
imaginative picture is changed. A poet might say that water runs downhill 
because it is attracted to the sea, but a physicist or an ordinary mortal 
would say that it moves as it does, at each point, because of the nature of 
the ground at that point, without regard to what lies ahead of it. Just as 
the sea does not cause the water to run towards it, so the sun does not cause 
the planets to move round it. The planets move round the sun because that is 
the easiest thing to do - in the technical sense of'least action'. It is the 
easiest thing to do because of the nature of the region in which they are, 
not because of an influence emanating from the sun.


The supposed necessity of attributing gravitation to a 'force' attracting the 
planets towards the sun has arisen from the determination to preserve 
Euclidean geometry at all costs. If we suppose that our space is Euclidean, 
when in fact it is not, we shall have to call in physics to rectify the 
errors of our geometry. We shall find bodies not moving in what we insist 
upon regarding as straight lines, and we shall demand a cause for this 
behaviour. Eddington stated this matter with admirable lucidity, and the 
following explanation is based on one given by him: Suppose that you assume 
the formula for interval which is used in the special theory of relativity - 
a formula which implies that your space is Euclidean. Since intervals can be 
compared by experimental methods, you will soon discover that your formula 
cannot be reconciled with the results of observation, and realise your The 
Abolition of 'Force' 135 mistake. If you insist on adhering to the Euclidean 
formula notwithstanding, then you will have to attribute the discrepancy 
between formula and observations to some influence which is present and which 
affects the behaviour of test bodies. You will introduce an additional agency 
to which you can attribute the consequences of your mistake. The name given 
to any agency which causes deviation from uniform motion in a straight line 
is force according to the Newtonian definition of force. Hence the agency 
invoked through your insistence on the Euclidean formula for interval is 
described as a 'field of force'.