or, obviously, it would be wholly incompatible with pure
agnosticism to suppose that we are capable of drawing any such
distinction in relation to the Divine activity itself. Even apart from
the theory of Theism, pure agnosticism must take it that the real
distinction is not between natural and supernatural, but between the
explicable and the inexplicable--meaning by those terms that which is
and that which is not accountable by such causes as fall within the
range of human observation. Or, in other words, the distinction is
really between the observable and the unobservable causal processes of
the universe.

Although science is essentially engaged in explaining, her work is
necessarily confined to the sphere of natural causation; beyond that
sphere (i.e. the sensuous) she can explain nothing. In other words,
even if she were able to explain the natural causation of everything,
she would be unable to assign the ultimate _raison d'etre_ of anything.

It is not my intention to write an essay on the nature of causality, or
even to attempt a survey of the sundry theories which have been
propounded on this subject by philosophers. Indeed, to attempt this
would be little less than to write a history of philosophy itself.
Nevertheless it is necessary for my purpose to make a few remarks
touching the main branches of thought upon the matter[50].

_The remarkable nature of the facts._ These are remarkable, since they
are common to all human experience. Everything that _happens_ has a
cause. The same happening has always the same cause--or the same
consequent the same antecedent. It is only familiarity with this great
fact that prevents universal wonder at it, for, notwithstanding all the
theories upon it, no one has ever really shown why it is so. That the
same causes always produce the same effects is a proposition which
expresses a fundamental fact of our knowledge, but the knowledge of this
fact is purely empirical; we can show no reason why it should be a fact.
Doubtless, if it were not a fact, there could be no so-called 'Order of
Nature,' and consequently no science, no philosophy, or perhaps (if the
irregularity were sufficiently frequent) no possibility of human
experience. But although this is easy enough to show, it in no wise
tends to show why the same causes should always produce the same
effects.

So manifest is it that our knowledge of the fact in question is only
empirical, that some of our ablest thinkers,