A Treatise of Human Nature · Chapter
Section III: Of the Other Qualities of Our Idea of Space and Time explained
Hume applies his principle that all ideas derive from impressions to the ideas of space and time.
What happens
Hume applies his principle that all ideas derive from impressions to the ideas of space and time. He argues that the idea of extension is a copy of the impressions of colored points or tangible atoms, and that abstract ideas are particular ideas considered in a certain light. Similarly, the idea of time is derived from the succession of perceptions, not from any distinct impression, and cannot be applied to unchangeable objects without a fiction. He also argues that indivisible points of space and moments of time must be filled with sensible qualities to be conceivable.
Themes in this chapter
Empiricism and the Primacy of Impressions
Hume applies the principle that all ideas derive from impressions to the ideas of space and time, arguing that they are copies of sensory impressions.
Skepticism About the External World
Hume's analysis reduces space and time to mere collections of perceptions, challenging the notion of an independent external reality.
Custom and General Rules
The formation of abstract ideas of space and time relies on custom and the habitual association of similar impressions.
Characters to notice
- David Hume
Author and narrator, presenting his philosophical arguments.
Key passages
“No discovery could have been made more happily for deciding all controversies concerning ideas, than that above-mentioned, that impressions always take the precedency of them, and that every idea, with which the imagination is furnished, first makes its appearance in a correspondent impression.”
The principle that impressions precede all ideas is the most useful discovery for settling disputes about ideas.
Hume reiterates his foundational empiricist principle.
“The table before me is alone sufficient by its view to give me the idea of extension. This idea, then, is borrowed from, and represents some impression, which this moment appears to the senses.”
The idea of extension comes from sensory impressions, like seeing a table.
Hume uses a concrete example to illustrate the origin of the idea of space.
“All abstract ideas are really nothing but particular ones, considered in a certain light; but being annexed to general terms, they are able to represent a vast variety, and to comprehend objects, which, as they are alike in some particulars, are in others vastly wide of each other.”
Abstract ideas are just particular ideas used generally, representing many similar objects.
Hume explains his nominalist theory of abstract ideas.
“The idea of time, being derived from the succession of our perceptions of every kind, ideas as well as impressions, and impressions of reflection as well as of sensations will afford us an instance of an abstract idea, which comprehends a still greater variety than that of space, and yet is represented in the fancy by some particular individual idea of a determinate quantity and quality.”
Time is an abstract idea derived from the succession of all perceptions, even more varied than space.
Hume introduces the idea of time as derived from succession.
“A man in a sound sleep, or strongly occupied with one thought, is insensible of time; and according as his perceptions succeed each other with greater or less rapidity, the same duration appears longer or shorter to his imagination.”
When we are asleep or focused, we don't perceive time; its length depends on the rate of our perceptions.
Hume illustrates that time is only perceived through succession.
“If you wheel about a burning coal with rapidity, it will present to the senses an image of a circle of fire; nor will there seem to be any interval of time betwixt its revolutions; merely because it is impossible for our perceptions to succeed each other with the same rapidity, that motion may be communicated to external objects.”
A fast-moving coal appears as a continuous circle because our perceptions can't keep up with the motion.
Hume uses this example to show that time perception depends on the speed of our perceptions.
