that mind is the product of matter, but their argument
nevertheless implies that some sort of material vehicle is
necessary for the continuance of mind in a future state of
existence. This material vehicle they seek to supply in the
theory which connects by invisible bonds of transmitted energy
the perishable material body with its counterpart in the world of
ether. The materialism of the argument is indeed partly veiled by
the terminology in which this counterpart is called a "spiritual
body," but in this novel use or abuse of scriptural language
there seems to me to be a strange confusion of ideas. Bear in
mind that the "invisible universe" into which energy is
constantly passing is simply the luminiferous ether, which our
authors, to suit the requirements of their hypothesis, have
gratuitously endowed with a complexity and variety of structure
analogous to that of the visible world of matter. Their language
is not always quite so precise as one could desire, for while
they sometimes speak of the ether itself as the "unseen
universe," they sometimes allude to a primordial medium yet
subtler in constitution and presumably more immaterial. Herein
lies the confusion. Why should the luminiferous ether, or any
primordial medium in which it may have been generated, be
regarded as in any way "spiritual"? Great physicists, like less
trained thinkers, are sometimes liable to be unconsciously
influenced by old associations of ideas which, ostensibly
repudiated, still lurk under cover of the words we use. I fear
that the old associations which led the ancients to describe the
soul as a breath or a shadow, and which account for the
etymologies of such words as "ghost" and "spirit," have had
something to do with this spiritualization of the interstellar
ether. Some share may also have been contributed by the Platonic