_Cambridge, August_ 18, 1758. I am as sorry as you seem to be that our
acquaintance harped so much on the subject of materialism when I saw him
with you in town. That we are indeed mechanical and dependent beings, I
need no other proof than my own feelings; and from the same feelings I
learn with equal conviction that we are not merely such; that there is a
power within that struggles against the force and bias of that
mechanism, commands its motion, and, by frequent practice, reduces it to
that ready obedience which we call "habit"; and all this in conformity
to a preconceived opinion, to that least material of all agents, a
thought.
I have known many in his case who, while they thought they were
conquering an old prejudice, did not perceive they were under the
influence of one far more dangerous; one that furnishes us with a ready
apology for all our worst actions, and opens to us a full licence for
doing whatever we please; and yet these very people were not at all the
more indulgent to other men, as they should have been; their indignation
to such as offended them was nothing mitigated. In short, the truth is,
they wished to be persuaded of that opinion for the sake of its
convenience, but were not so in their heart.