Hume's theory of causation and necessity

¶ … Hume think that causation is not necessary connection?

In setting the stage for understanding Hume's theory of causation, and at the same time understanding why causation does not necessarily a connection, an overview of his causation theory is worthwhile. Hume makes a sharp distinction between the two ways in which the mind constructs ideas; there are impressions and ideas, and within those contexts there are natural relations and philosophical relations. Hume explains the three natural relations as contiguity, resemblance, and cause and effect, and the philosopher points to causation as the most common of the three natural relations. The fact that humans come to believe in certain facts that go "…beyond the present testimony of our senses and memory" verifies Hume's theory of causation, according to Chapter 15 (408).

The examples given -- a watch found on a desert island [cause] leads to the belief [effect] that a human was there, and a voice in a dark room [cause] suggests another person is there [effect] -- shows Hume's belief that cause and affect transcends what memory and sense otherwise bring to the human mind. But he also says that humans' belief in cause and effect, and that events are related to one another by cause and effect, is not rational (410). Even though it is very common and understandable for humans to believe a second event is a result of the first, without this common cause and effect assumption, humans would be "…entirely ignorant of every matter of fact" beyond what is immediately obvious and present (410).

The author (Chapter 15) condenses Hume's approach to cause as "…a kind of fiction" because there "…are no necessary connections anywhere" when it comes to experiences, there are simply impressions. Beliefs that things are connected are based on "habit" which boils down to experience; causes are based on: a) when one object precedes and is contiguous to another; and b) when the idea of one object of event leads to the impression that there will be another object or event following the first.

Why does Hume believe causation is not necessarily connection? "…there are no ideas, which occur in metaphysics, more obscure and uncertain, than those of power, force, energy or necessary connection" (Treatise of Ideas, 61-2). He does not go along with what many philosophers see as necessary connections between ideas and facts. He believes humans cannot get a good idea of what is necessary connection simply by experiencing it through sensory experiences. That is because internal experiences (i.e., sensory experiences) are too hard to nail down, and with internal experiences there is nothing with which to make a solid connection.

Humans are constantly bombarded with the coming together of two events, to put it another way. When event "C" occurs our experiences relate to our consciousness that "D" will follow "C" because in the past events like "D" have always followed "C" events. Humans expect that to happen, Hume explains, because they have in the past and so humans have an expectation that C. will generally be followed by D. This, Hume writes, is our impression from which the idea of connection is presented in our minds. The events themselves do not necessarily make it true, partly because our perceptions of objects and events are not joined in reality, and they have no unity in and of their own existence, he explains.

As to experience, Hume asserts (419) that the most experience can yield for a person is "probability," and if a cause is only known based on its effect, "…we never ought to ascribe to it any qualities, beyond what are precisely requisite to produce the effect" (Hume, 420).

A good example as to why causation isn't always connected is found on page 420. Hume asserts that only when two objects are "constantly conjoined" can observers "infer the one from the other." But rarely are two effects and two causes connected, Hume continues. If a cause and effect have "resemblance" to another cause and effect, they can be conjoined, but that is rare indeed.

Put into simpler words, Hume doubts that even with a repetition of conjunctions it would be safe to believe a "connection" between the cause and effect would be established. Indeed, after a person experiences sees instances repeated repetitiously, the mind is convinced through the person's habits and reflections that upon the introduction of one event, another event is expected to happen, and humans believe this will happen. His own explanation is that a cause is an "…object followed by another, and whose appearance always conveys the thought to that other"; but, as earlier noted, this situation does not necessarily imply a connection.

Hume's metaphysics of perception (impressions, ideas, simple and complex ones).

Perceptions, Hume believes, are independent:

"Now as every perception is distinguishable from another, and may be considered as separately existent; It evidently follows, that there is no absurdity in separating

any particular perception from the mind…that is, in breaking off all its relations with that connected mass of perceptions which constitute a thinking being"

(Treatise, 207).

What he is getting at here regarding perception (on page 207 of his Treatise) is that the mind is "…nothing but a heap or collection of different perceptions." In fact Hume goes on to suggest that perceptions are not owned by anyone, rather, they are just floating out there in space. On page 202 of his Treatise, he distinguishes between perceptions that are dependent on the mind, and the objects that created the perception which are not dependent on the mind's ability to perceive: