extrinsic. The separation of it often requires great attention,
accuracy, and subtilty.

6. The forming of general maxims from particular observation is
a very nice operation; and nothing is more usual, from haste or
a narrowness of mind, which sees not on all sides, than to
commit mistakes in this particular.

7. When we reason from analogies, the man, who has the greater
experience or the greater promptitude of suggesting analogies,
will be the better reasoner.

8. Byasses from prejudice, education, passion, party, &c. hang
more upon one mind than another.

9. After we have acquired a confidence in human testimony,
books and conversation enlarge much more the sphere of one
man's experience and thought than those of another.

It would be easy to discover many other circumstances that make
a difference in the understandings of men.

85. But though animals learn many parts of their knowledge from
observation, there are also many parts of it, which they derive from the
original hand of nature; which much exceed the share of capacity they
possess on ordinary occasions; and in which they improve, little or
nothing, by the longest practice and experience. These we denominate
Instincts, and are so apt to admire as something very extraordinary, and
inexplicable by all the disquisitions of human understanding. But our
wonder will, perhaps, cease or diminish, when we consider, that the