The Understanding

For Hume, the understanding is that part of the mind that is conscious and its associated mechanisms.

Impressions

Sense-data that human consciousness confronts directly and that is represented by other mental entities.

Ideas

Ideas are the mental entities that represent impressions and those that are stored by the mind.

Relations

Relations are a series of basic categories for comparing ideas to impressions, impressions to impressions and ideas to ideas.

Pleasure and Pain

Hume sees pleasure and pain at the root of the passions, moral judgments, and moral distinctions.

The Indirect Passions

Passions that related impressions to the self or other persons, such as pride, humility, anger, etc.

Reason

Hume thinks that reasoning alone cannot motivate us, only when supplemented by the passions. Hume famously argued that reason was the slave of the passions.

Belief

For Hume, a belief is a impression with significant 'force and vivacity...