In An Inquiry Concerning Human Understanding, David Hume demonstrates how there
is no way to rationally make any claims about future occurrences. According to
Hume knowledge of matters of fact come from previous experience. From building
on this rationale, Hume goes on to prove how, as humans we can only make
inferences on what will happen in the future, based on our experiences of the
past. But he points out that we are incorrect to believe that we are justified
in using our experience of the past as a means of evidence of what will happen
in the future. Since we have only experience of the past, we can only offer
propositions of the future. Hume classifies human into two categories;
“Relations of Ideas,” and “Matters of Fact.” (240) “Relations of
ideas” are either intuitively or demonstratively certain, such as in
Mathematics (240). It can be affirmed that 2 + 2 equals 4, according to Hume’s
“relations of ideas.” “Matters of fact” on the other hand are not
ascertained in the same manner as “Relations of Ideas.” The ideas that are
directly caused by impressions are called "matters of fact". With
“matters of fact,” there is no certainty in establishing evidence of truth
since every contradiction is possible. Hume uses the example of the sun rising
in the future to demonstrate how as humans, we are unjustified in making
predictions of the future based on past occurrences. As humans, we tend to use
the principle of induction to predict what will occur in the future. Out of
habit, we assume that sun will rise every day, like it has done in the past, but
we have no basis of actual truth to make this justification. By claiming that
the sun will rise tomorrow according to Hume is not false, nor is it true. Hume
illustrates that “the contrary of every matter of fact is still possible,
because it can never imply a contradiction and is conceived by the mind with the
same facility and distinctness as if ever so conformable to reality” (240).
Just because the sun has risen in the past does not serve as evidence for the
future. Thus, according to Hume, we are only accurate in saying that there is a
fifty- percent chance that the sun will rise tomorrow. Hume felt that all
reasoning concerning matter of fact seemed to be founded on the relation between
cause and effect. (241) Hume said that even though the cause preceded the
effect, there is no proof that the cause is responsible for the effect's
occurrence , it could be purely coincidental. He claims that the human notion of
cause and effect is ungrounded in empirical evidence, but rather given only
reasonable probability through continuous reinforcement. Hume's rejection of
causation implies a rejection of scientific laws, which are based on the general
premise that one event necessarily causes another and predictably always will.
According to Hume's philosophy, therefore, knowledge of matters of fact is
impossible, although as a practical matter he freely acknowledged that people
had to think in terms of cause and effect, and had to assume the validity of
their perceptions, For example, if I touch the hot stove, I will get burnt. This
statement does not necessitate that when I touch the hot stove, (cause) I will
always get burnt (effect). Instead, according to Hume, I have no good reason to
think that it will not happen again. Hume, however, went further, endeavoring to
prove that reason and rational judgments are merely habitual associations of
distinct impressions or experiences. Hume claims that all our ideas, which form
the basis of our knowledge, are derived from impressions that we take in from
the outside world and into the inside world of our mind. Hume grouped
perceptions and experiences into one of two categories: impressions and ideas.
(238) According to Hume, ideas are memories of sensations but impressions are
the cause of the sensation. An impression is part of a temporary feeling, but an
idea is the permanent impact of this feeling. Hume believed that ideas were just
dull imitations of impressions. Hume did not believe that a priori, knowledge
based on reasoning can deduce true knowledge. Knowledge based on reasoning
alone, according to Hume does not provide understanding of the real world. He
believed that all ideas have to have impressions, that the human mind invented
nothing. So, according to Hume, a priori reasoning does not offer any
understanding of the real world, because they cannot be traced to the
impressions that first created them. The human mind takes simple ideas, and
turns them into complex ideas. (243) An example of this concept is the idea of
an unicorn. Unicorns are conceived as being horses with horns. Hume’s claimed
that an unicorn is formed of two simple ideas, the figure of a horse and a horn.
Hume concludes that our beliefs can never be rationally justified, but must be
acknowledged to rest only upon our acquired habits. In similar fashion, Hume
argued that we cannot justify our natural beliefs in the reality of the self or
the existence of an external world. From all of this, he concluded that a severe
skepticism is the only defensible view of the world, though he does not expect
us to live our daily lives by this notion. Wesley C. Salmon points out that
according to the principle of uniformity of nature that even though we do not
know for sure what will happen in the future, we must assume that nature will
continue as it has done in the past. This is the human condition, in that we
have no way of asserting what will happen in the future. But in living our daily
lives, we are better to go by what has occurred in the past in nature, despite
Hume’s philosophy that there is only a 50/50 chance. In order to function, we
need to accept that there is a uniformity of nature in order to carry on with
our lives.
Bibliography 1. Reason & Responsibility. Ed. Joel Feinberg & Russ Shafer- Landau.
Belmont, CA:Wadsworth Publishing Company, 1999.