oduces
the opinion of their continued existence. When I return to my chamber
after an hour's absence, I find not my fire in the same situation, in
which I left it: But then I am accustomed in other instances to see a
like alteration produced in a like time, whether I am present or absent,
near or remote. This coherence, therefore, in their changes is one of
the characteristics of external objects, as well as their constancy.

Having found that the opinion of the continued existence of body depends
on the COHERENCE, and CONSTANCY of certain impressions, I now proceed to
examine after what manner these qualities give rise to so extraordinary
an opinion. To begin with the coherence; we may observe, that though
those internal impressions, which we regard as fleeting and perishing,
have also a certain coherence or regularity in their appearances, yet
it is of somewhat a different nature, from that which we discover in
bodies. Our passions are found by experience to have a mutual connexion
with and dependence on each other; but on no occasion is it necessary
to suppose, that they have existed and operated, when they were not
perceived, in order to preserve the same dependence and connexion, of
which we have had experience. The case is not the same with relation
to external objects. Those require a continued existence, or otherwise
lose, in a great measure, the regularity of their operation. I am here
seated in my chamber with my face to the fire; and all the objects, that
strike my senses, are contained in a few yards around me. My memory,
indeed, informs me of the existence of many objects; but then this
information extends not beyond their past existence, nor do either my
senses or memory give any testimony to the continuance of their being.
When therefore I am thus seated, and revolve over these thoughts, I hear
on a sudden a noise as of a door turning upon its hinges; and a little
after see a porter, who advances towards me. This gives occasion to many
new reflections and reasonings. First, I never have observed, that
this noise coued proceed from any thing but the motion of a door; and
therefore conclude, that the present phaenomenon is a contradiction to
all past experience, unless the door, which I remember on the other side
the chamber, be still in being. Again, I have always found, that a human
body was possest of a quality, which I call gravity, and which hinders
it from mounting in the air, as this porter must have