authenticate them.

Our first knowledge is acquired by our senses; but these are liable to
deceive us, and we learn to detect these deceptions by comparing the ideas
presented to us by one sense with those presented by another. Thus when we
first view a cylinder, it appears to the eye as a flat surface with
different shades on it, till we correct this idea by the sense of touch,
and find its surface to be circular; that is, having some parts gradually
receding further from the eye than others. So when a child, or a cat, or a
bird, first sees its own image in a looking-glass, it believes that another
animal exists before it, and detects this fallacy by going behind the glass
to examine, if another tangible animal really exists there.

Another exuberant source of error consists in the false notions, which we
receive in our early years from the design or ignorance of our instructors,
which affect all our future reasoning by their perpetual intrusions; as
those habits of muscular actions of the face or limbs, which are called
tricks, when contracted in infancy continue to the end of our lives.

A third great source of error is the vivacity of our ideas of imagination,
which perpetually intrude themselves by various associations, and compose
the farrago of our dreams; in which, by the suspension of volition, we are
precluded from comparing the ideas of one sense with those of another, or
the incongruity of their successions with the usual course of nature, and
thus to detect their fallacy. Which we do in our waking hours by a
perpetual voluntary exertion, a process of the mind above mentioned, which
we have termed intuitive analogy. Sect. XVII. 3. 7.

This analogy presupposes an acquired knowledge of things, hence children
and ignorant people are the most credulous, as not possessing much
knowledge of the usual course of nature; and secondly, those are most
credulous, whose faculty of comparing ideas, or the voluntary exertion of
it, is slow or imperfect. Thus if the power of the magnetic needle of
turning towards the north, or the shock given by touching both sides of an
electrized coated jar, was related for the first time to a philosopher, and
to an ignorant person; the former would be less ready to believe them, than
the latter; as he would find nothing similar in nature to compare them to,
he would again and again repeat the experiment, before he would give it his
entire credence; till by these repetitions it would ce