no respect, different from them. Reason is incapable of any such
variation. The conclusions which it draws from considering one
circle are the same which it would form upon surveying all the circles
in the universe. But no man, having seen only one body move after
being impelled by another, could infer that every other body will move
after a like impulse. All inferences from experience, therefore, are
effects of custom, not of reasoning.*

  * Nothing is more useful than for writers, even, on moral,
political, or physical subjects, to distinguish between reason and
experience, and to suppose, that these species of argumentation are
entirely different from each other. The former are taken for the
mere result of our intellectual faculties, which, by considering
priori the nature of things, and examining the effects, that must
follow from their operation, establish particular principles of
science and philosophy. The latter are supposed to be derived entirely
from sense and observation, by which we learn what has actually
resulted from the operation of particular objects, and are thence able
to infer, what will, for the future, result from them. Thus, for
instance, the limitations and restraints of civil government, and a
legal constitution, may be defended, either from reason, which
reflecting on the great frailty and corruption of human nature,
teaches, that no man can safely be trusted with unlimited authority;
or from experience and history, which inform us of the enormous
abuses, that ambition, in every age and country, has been found to
make of so imprudent a confidence.

  The same distinction between reason and experience is maintained
in all our deliberations concerning the conduct of life; while the
experienced statesman, general, physician, or merchant is trusted
and followed; and the unpractised novice, with whatever natural
talents endowed, neglected and despised. Though it be allowed, that
reason may form very plausible conjectures with regard to the
consequences of such a particular conduct in such particular
circumstances; it is still supposed imperfect, without the
assistance of experience, which is alone able to give stability and
certainty to the maxims, derived from study and reflection.

  But notwithstanding that this distinction be thus universally
received, both in the active speculative scenes of life, I shall not
scruple to pronounce, that it is, at bottom, erroneous, at least,
superficial.

  If we examine those arguments, which, in any of the sciences above
mentioned, are supposed to be mere effects of reasoning and
reflection, they will be found to terminate, at last, in some
general principle or conclusion, for which we can assign no reason but
observation and experience. The only difference between them and those
maxims, which are vulgarly esteemed the result of pure experience, is,
that the former cannot be established without some process of thought,
and some reflection on what we have observed, in order to
distinguish its circumstances, and trace its consequences: Whereas
in the latter, the experienced event is exactly and fully familiar
to that which we infer as the result of any particular situation.
The history of a Tiberius or a Nero makes us dread a like tyranny,
were our monarchs freed from the restraints of laws and senates: But
the observation of any fraud or cruelty in private life is sufficient,
with the aid of a little thought, to give us the same apprehension;
while it serves as an instance of the general corruption of human
nature, and shows us the danger which we must incur by reposing an
entire confidence in mankind. In both cases, it is experience which is
ultimately the foundation of our inference and conclusion.

  There is no man so young and unexperienced, as not to have formed,
from observation, many general and just maxims concerning human
affairs and the conduct of life; but it must be confessed, that,
when a man comes to put these in practice, he will be extremely liable
to error, till time and farther experience both enlarge these
maxims, and teach him their proper use and application. In every
situation or incident, there are many particular and seemingly
minute circumstances, which the man of greatest talent is, at first,
apt to overlook, though on them the justness of his conclusions, and
consequently the prudence of his conduct, entirely depend. Not to
mention, that, to a young beginner, the general observations and
maxims occur not always on the proper occasions, nor can be
immediately applied with due calmness and distinction. The truth is,
an unexperienced reasoner could be no reasoner at all, were he
absolutely unexperienced; and when we assign that character to any
one, we mean it only in a comparative sense, and suppose him possessed
of experience, in a smaller and more imperfect degree.

  Custom, then, is the great guide of human life. It is that principle
alone which renders our experience useful to us, and makes us
expect, for the future, a similar train of events with those which
have appeared in the past. Without the influence of custom, we
should be entirely ignorant of every matter of fact beyond what is
immediately present to the memory and senses. We should never know how
to adjust means to ends, or to employ our natural powers in the
production of any effect. There would be an end at once of all action,
as well as of the chief part of speculation.

  37. But here it may be proper to remark, that though our conclusions
from experience carry us beyond our memory and senses, and assure us
of matters of fact which happened in the most distant places and
most remote ages, yet some fact must always be present to the senses
or memory, from which we may first proceed in drawing these
conclusions. A man, who should find in a desert country the remains of
pompous buildings, would conclude that the country had, in ancient
times, been cultivated by civilized inhabitants; but did nothing of
this nature occur to him, he could never form such an inference. We