What did David Hume argue about cause and effect?

David Hume argued that the idea of causation consists of three components: the contiguity of events in time and space, the temporal priority of the cause, and a "necessary connection" between them.12

While we observe contiguity and succession in experience, Hume noted that we never directly observe a "necessary connection" in the objects themselves. Instead, this idea is subjective, arising from the mind's habit of expecting a familiar effect after experiencing a constant conjunction of events.12

Because we cannot logically justify the assumption that the future will resemble the past, Hume concluded that causal inferences are not based on reason but are instead the result of custom and psychological compulsion. This skepticism forms the basis of the problem of induction, as Hume maintained that while we are naturally driven to form beliefs about cause and effect, these beliefs remain rationally unjustified.13