Understanding Hume’s theory of space and time requires suspending our own. When
theorizing, we think of space as one huge array of locations, which external objects
might or might not occupy. Time adds another dimension to this vast array.
For Hume, in contrast, space is extension in general, where being extended is having
parts arranged one right next to the other like the pearls on a necklace. Time is duration
in general, where having duration is having parts occurring one aft er another like the
notes of a song. Hume’s diff erent view stems from his empiricism, his reliance on experience
and observation as the foundation of our concepts. Nothing in our experience
suggests a single vast array of locations. Rather, we simply notice that bodies are similar
insofar as they have lengths that can be compared. Likewise, nothing in our experience
suggests a single dimension of time. Rather, we simply notice that diff erent successions
are similar insofar as they have durations that can be compared. Th eorizing that these
observations show there to be a single multidimensional array goes well beyond the evidence
for Hume. As a skeptic, he fi nds himself unable to assent to theories that stray too
far beyond the deliverances of the senses.
For Hume, the ideas of space and time are each a general idea of simple—partless—
objects arrayed in a certain manner. He argues that the structures of the ideas of space
and time refl ect the structures of space and time. Th erefore, space and time are not infi -
nitely divisible, and they are ways simple objects are arrayed. Consequently, there is no
such thing as empty space nor time without change.