He says knowledge comes from sense impressions, and ideas are a copy;
they are less clear and intense than the original impression. The mind
brings thoughts via their association, what he calls "a principle of
connection." They resemble contiguity, cause, and results. There are two
different ways to justify a causal case: relations of thoughts or
matters of truth. For example, "This room doesn't have four walls" isn't
problematic; the room could have three walls. The authenticity of any
statement relies upon its establishment in experience or the memory of
the experience. Hume argues that the possibility of a causal connection
joining one event with another is just a psychological habit. The
conviction that the sun will rise tomorrow connects with the level of
probability that it will. Since he denies information on causation, Hume
doesn't feel that things occur by coincidence. Belief in probability
judgments communicates a degree of certainty about a future event. The
hypothesis of Hume contends that human activity is administered by
regular regulations, similarly as normal occasions are represented by
regulations. Human thought processes are not really associated with
their activities, but rather, Hume contends, they are continually
conjoined.
