world. The immense growth of scientific knowledge during the last
century was bound to react on human conceptions of scientific procedure.
The enormous number of new facts brought to light by manipulating
hypotheses could not but modify our view of scientific law. Laws no
longer seem to scientists the immutable foundations of an eternal order,
but are inevitably treated as man-made formulae for grouping and
predicting the events which verify them. The labours of physicists like
Mach, Duhem, and Ostwald, point to alternative formulations of new
hypotheses for the best established laws. The physics of Newton are no
longer final, and the notion of 'energy' is a dangerous rival to the
older conception of 'matter.' It is, of course, indifferent to the
philosopher whether the new physics are successful in superseding the
old or not. What it concerns him to note is that dogmatic confidence in
the finality of scientific laws has given place to a belief that our
"laws" are only working formulae for scientific purposes, and that no
science can truly boast of having read off the mind of the Deity. As Sir
J.J. Thomson neatly puts it, a scientific theory, for the enlightened
modern scientist, is a 'policy and not a creed.' Science has become
content to be only 'a conceptual shorthand,' provided that its message
be humanly intelligible. It no longer claims truth because abstractly
and absolutely it 'corresponds with Nature,' but because it yields a
convenient means of mastering the flux of events.

Even mathematics, long the pattern of absolute knowledge, has not
escaped the stigma of relativity. 'Metageometries' have been invented by
Riemann and Lobatschewski as rivals to the assumptions of Euclid, and
the brilliant writings of Poincaré have explained the human devices on
which mathematical concepts rest. Euclidean geometry is reduced to a
useful interpretation of the data of experience; it is not theoretically
the only one. Its superior validity is dependent upon its use when