mena in
constant and direct relation--phenomena that follow visibly and
immediately after their antecedents--phenomena of which the causation is
neither remote nor obscure--phenomena which may be predicted by the
simplest possible act of reasoning.

If, now, we pass to the previsions constituting what is commonly known
as science--that an eclipse of the moon will happen at a specified time;
and when a barometer is taken to the top of a mountain of known height,
the mercurial column will descend a stated number of inches; that the
poles of a galvanic battery immersed in water will give off, the one an
inflammable and the other an inflaming gas, in definite ratio--we
perceive that the relations involved are not of a kind habitually
presented to our senses; that they depend, some of them, upon special
combinations of causes; and that in some of them the connection between
antecedents and consequents is established only by an elaborate series
of inferences. The broad distinction, therefore, between the two orders
of knowledge, is not in their nature, but in their remoteness from
perception.

If we regard the cases in their most general aspect, we see that the
labourer, who, on hearing certain notes in the adjacent hedge, can
describe the particular form and colours of the bird making them; and
the astronomer, who, having calculated a transit of Venus, can delineate
the black spot entering on the sun's disc, as it will appear through the
telescope, at a specified hour; do essentially the same thing. Each
knows that on fulfilling the requisite conditions, he shall have a
preconceived impression--that after a definite series of actions will
come a group of sensations of a foreknown kind. The difference, then, is
not in the fundamental character of the mental acts; or in the
correctness of the previsions accomplished by them; but in the
complexity of the processes required to achieve the previsions. Much of
our commonest knowledge is, as far as it goes, rigorously precise.
Science does not increase this precision; cannot transcend it. What then
does it do? It reduces other knowledge to the same degree of precision.
That certainty which direct perception gives us respecting coexistences
and sequences of the simplest and most accessible kind, science gives us
respecting coexistences and sequences, complex in their dependencies or
inaccessible to immediate observation. In brief, regarded from this
point of view, science may be c