A METAPHYSICAL DISCUSSION 227 



The Description oi Nature. Now we go a step further. Our 

 life intuition, disappearing as such, inserts matter and energy 

 into nature. Or, rather, it does not create matter, so much 

 as pass over into it. That is what we should have said twenty 

 years ago, but can we say it now ? Obviously not. 



For we do not really observe matter and energy in nature. 

 We observe space-time coincidences, and from these we infer' 

 space and time measurements. It is not matter, nor even energy, 

 that we infer it is only space-time measurements or intervals. 

 That is our " second approximation," but we can go further still, 

 thanks to the modern, generalised theory of relativity. That 

 which we know as " nature " is not matter and energy, nor even 

 space and time, but the relations between space-time coincidences. 



What is the "weather" ? Intuitively it is a feeling of dis- 

 comfort, but we " know " it and describe it, and act upon it (or 

 are acted upon by it, when the " sign " of the action is changed) 

 in strictly materialistic ways: it is rain and wind and a low 

 temperature and mist. Looking into the matter more closely, 

 we find, for instance, that the low barometer is one of the terms 

 in our description, and the quantity of water in the rain gauge is 

 another. But these are space measurements, for the low baro- 

 meter is a column of mercury (a linear dimension) of a certain 

 magnitude, and the rain-gauge observation is a volume of water 

 (a cubic dimension). The temperature is also a linear dimension 

 the length of a mercury, capillary column. Coupled with these 

 observations there are time ones: we read barometer, rain gauge, 

 and thermometer at a certain instant when the hands of the 

 clock had moved through a certain arc (since the last twelve noon 

 or midnight). Obviously the time is a space measurement. 



So, also, the material water, nitrogen, and oxygen in the 

 environment are time and space measurements. Whatever they 

 feel to us that is, whatever our intuition of them may be we 

 describe them as molecules which are made up of atoms which 

 we regard as electrons in movement. And of the electrons we can 

 know nothing but space measurements : a positive nucleus with 

 several electrons and a surrounding swarm of negative ones; 

 relative velocities and stresses, repulsions and attractions. The 

 " actual " molecule, or atom, or electron, moves; thus we have, 

 coupled with positions, instants in time. 



That is, our knowledge of nature is space and time measure- 

 ment, and, indeed, we can see no distinction between the measure- 

 ment of space and that of time. We do not know space and time 

 intellectually, for space is the intuitive knowledge of our freedom 



