How did David Hume explain the association of ideas?

David Hume explained that while the imagination has the capacity to assemble or divide ideas at will, human thought typically follows regular and predictable patterns guided by three principles of association: resemblance, contiguity, and cause and effect.1

• Resemblance: The mind is naturally inclined to move from one idea to another that shares similar qualities, such as transitioning from thoughts of a dog to a wolf or coyote.1
• Contiguity: People tend to associate ideas of things that are near each other in space or time.1
• Cause and Effect: This is the most significant principle, where the mind connects ideas of events that are frequently and uniformly observed together.12

Hume argued that these associations are not based on intrinsic logical connections in nature but are instead the product of "mental habit". When we perceive events as causally linked, we are actually experiencing a habitual association formed by the "constant conjunction" of those events in our minds. Consequently, the feeling of necessity we attribute to these connections is merely a subjective feeling of compulsion arising from this psychological habit.32