h the strongest opposition
from the prejudices of the learned, and from the superstition of those
who judge not for themselves in forming their notions, but look up to
men of science for authority. Such is the case with some part of the
Theory of the Earth, which I have given, and which will probably give
offence to naturalists who have espoused an opposite opinion. In order,
then, to obtain the approbation of the public, it may not be enough to
give a theory that should be true, or altogether unexceptionable it may
be necessary to defend every point that shall be thought exceptionable
by other theorists, and to show the fallacy of every learned objection
that may be made against it. It is thus, in general, that truth and
error are forced to struggle together, in the progress of science; and
it is only in proportion as science removes erroneous conceptions, which
are necessarily in the constitution of human knowledge, that truth will
find itself established in natural philosophy.

Mr Kirwan has written a dissertation, entitled, _Examination of the
Supposed Igneous Origin of Stony Substances_, which was read in the
Royal Irish Academy. The object of that dissertation is to state certain
objections, which have occurred to him, against the Theory of the Earth
published in the Transactions of the Edinburgh Royal Society; and he has
attacked that theory in all the points where it appears to him to be
vulnerable. It is to these objections that I am now to give an answer.
The authority given to this dissertation, by the Royal Irish Academy,
as well as the reputation of the author, make it necessary for me
to endeavour to put in their true light the facts alleged in that
performance, and to analyse the arguments employed, in order to judge of
the reasoning by which the theory of mineral fusion is refuted in this
Examination.

A theory founded on truth, and formed according to the proper rules of
science, can ever suffer from a strict examination, by which it would
be but the more and more confirmed. But, where causes are to be traced
through a chain of various complicated effects, an examination not
properly conducted upon accurate analytical principles, instead of
giving light upon a subject in which there had been obscurity and doubt,
may only serve to perplex the understanding, and bring confusion into a
subject which was before sufficiently distinct. To redress that evil,
then, must require more labour and some address; an