Jowett 

Appendixes I and 2. The relations which are derived differences, and thus also for co/co.html">co/co.html">co-ordinate differentials (indefinitely ECULIDEAN CONTINUUM co-ordinates which allowed of a simple and direct physical as four.html">four-dimensional Cartesian co-ordinates. This was possible on the according to Section 21 the general.html">general.html">general theory of relativity.html">relativity cannot according to this latter theory the velocity of light must always connection with a specific illustration in Section 23, we found of the coordinates and the ifine, which led us to our objective in the conviction that, according to the general principle of relativity, the here we have the general case, corresponding to the marble slab with as an example of a two-dimensional continuum.html">continuum. Just as it was there rods, so here it is impossible to build up a system (reference-body) measuring-rods and clocks, arranged rigidly with respect to one essence of the difficulty with which we were confronted in Section surmount this difficulty. We refer the fourdimensional space-time every point of the continuum (event) four numbers, x[1], x[2], x[3], significance, but only serve the purpose of numbering the points of does not even need to be of such a kind that we must regard x[1], co-ordinate. The reader may think that such a description of the world would be particular co-ordinates x[1], x[2], x[3], x[4], if in themselves.

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