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Thus all our previous conclusions based on general relativity

would appear to be called in question. In reality we must make a

subtle detour in order to be able to apply the postulate of

general relativity exactly. I shall prepare the reader for this

in the following paragraphs.

XXIV.

EUCLIDEAN AND NON-EUCLIDEAN CONTINUUM

The surface of a marble table is spread out in front of me. I can

get from any one point on this table to any other point by

passing continuously from one point to a "neighbouring" one, and

repeating this process a (large) number of times, or, in other

words, by going from point to point without executing "jumps." I

am sure the reader will appreciate with sufficient clearness what

I mean here by "neighbouring" and by "jumps" (if he is not too

pedantic). We express this property of the surface by describing

the latter as a continuum.