- David Hume
David Hume was born on May 7, 1711 and he died on August 25, 1776. He was a Scottish
enlightenment philosopher in the 18th century, along with a historian, librarian, economist
and essayist. Today he is most well-known for his works in empiricism, skepticism and
naturalism.
Hume opposed rationalism which is the epistemological view that claims that there are
significant ways in which our concepts and knowledge are gained independently of sense
experience. Rationalists believed in reasoning as the main source of knowledge.
- Empiricism
Empiricism is the view that all knowledge is derived primarily from human senses
particularly through observations and experiments as it relates to sensory perceptions,
rather than resting solely on a priori reasoning, intuition and theoretical speculation.
There is an emphasis on the importance of experience for human knowledge and a
tendency to doubt that which cannot be established on the basis of the evidence of the
senses.
Empiricism is founded on two basic principles: first that all ideas are derived from
experience, and second, that proper judgement must be supported by experience. Hume as
well as other empiricists, held that we have two kinds of experience: sensation, or external
experience, and reflection, or internal experience.
These two kinds of experience were held to provide the foundations of all knowledge.
Knowledge of necessary truths, such as the truths of logic and mathematics, were held to
derive from inner experience of the relations among ideas, while empirical knowledge of
contingent truths was held to derive from the outer experience of the senses of vision,
hearing, smell, taste and touch.
Empiricism emphasizes the role of empirical evidence in the formation of ideas, rather
than innate ideas or traditions. However, empiricists may argue that traditions (or customs) arise
due to relations of previous sense experiences.
Hume maintained that no knowledge, even the most basic beliefs about the natural world, can be
conclusively established by reason. Rather, he maintained, our beliefs are more a result of
accumulated habits, developed in response to accumulated sense experiences.
He claims that all of our knowledge must be derived from impressions that come either
from our outer senses (sight, hearing, touch, taste, smell) or from our inner senses (our
inner feelings, such as anger, sorrow, pain). Consequently, we cannot have genuine
knowledge of a thing unless we can point to the impression from which the idea of that
thing is derived.
- Impressions and ideas
Hume’s first philosophy states "no beings are ever present to the mind but
perceptions." Hume resolved the perceptions of the human mind into two distinct
kinds, which he called impressions and ideas. He gives priority and precedence to
the impressions
Impressions are the actual experiences and sensations (for e.g., tasting an apple or
watching a sunset) whereas ideas are weaker recollections of those impressions (for
e.g., memory of the taste of an apple or the idea or picture of a sunset).
Impressions are of two kinds, impressions of sensations, also called original impressions, or
impressions of reflection, also called secondary impressions. Impressions of sensations
include the feelings we get from our five senses as well as pains and pleasures. These are
called original because trying to determine their ultimate causes would take us beyond
anything we can experience. Impressions of reflection include desires, emotions, passions
and sentiments. They are essentially reactions or responses to ideas.
Ideas can combine impressions to form new ideas. This is how imagination works.
For e.g., you might imagine a golden mountain when you read it somewhere or
maybe just now when I said it, but you have never actually seen one. You’re still able
to imagine it because you might have seen gold and you might have seen a
mountain, then you combine them both to see a golden mountain.
Hume accepts that ideas may be either the product of mere sensation or of the imagination
working in conjunction with sensation. According to Hume, our minds make use of four mental
operations that produce imaginings out of sense-impressions. These operations
are compounding (adding one idea to another) (or the addition of one idea onto another, such as
a horn on a horse to create a unicorn); transposing (or the substitution of one part of a thing with
the part from another, such as with the body of a man upon a horse to make
a centaur); augmenting (taking one idea and adding to it) (as with the case of a giant, whose size
has been augmented); and diminishing (as with Lilliputians, whose size has been diminished).
(Hume 1974:317)
Every idea we have in our heads, Hume claimed, has to come from some earlier sense
impression or a combination of impressions. Therefore, the senses are the source of all our
knowledge
- Sense uncertainty – Skepticism
Hume’s empiricism led him to his skepticism which is the belief that true knowledge is
unattainable.
It is evident that the reason Hume's philosophy leads all the way to uncertainty and
ends in sceptical philosophy is due to his first principle that stated, "no beings are
ever present to the mind but perceptions.". Instead of making thought a part of being,
he enclosed all being in thought, making mind, to be nothing but a heap of
perceptions. Due to this he thought we could never be certain of what humans and
our sense experience are so we, as humans, can never be sure about our
knowledge, as it is all what we gain from experiences and our perceptions.
Hume states, ultimately, we are heavily restricted on what facts we can think
because these ideas must be based on direct sense impressions. Most importantly
he says that complex ideas must be viewed with scepticism because while we can
explain their formation, we cannot prove their reality.
In the Inquiry Hume maintains the same view regarding the senses. He has been
dealing with the scepticism that arises from science and inquiry. The arguments of
the sceptics are presented against the evidence of sense, such as the imperfection
and fallaciousness of our sense organs on many occasions such as the crooked
appearance of an oar in the water; the deceptive appearance of objects viewed from
various distances (like how the sun looks small from a distance), and the double
image which comes from pressing one eye, and many other similar appearances.
These arguments of the sceptics according to Hume,, are evidence enough to show
that the senses alone are not to be implicitly depended upon.
We can never really be fully sure of something because if knowledge comes from our senses
or sensory experiences, we are limited to our experiences because we never really
experience everything, such as all the events that happen between the cause and an effect.
David Hume argued that we could not empirically demonstrate the existence of causality
- Cause and effect
Hume states that everything we know is based on experience and cause and effect for e.g.,
we eat food, and we stop getting hungry, we put a pot of water over fire and the water
eventually boils. We never have any real guarantee that it will happen again in the future.
We don’t see a link and only see a correlation. Take for example this event - (Ball A moves,
ball A hits ball B, ball B begins to move) The effect is not necessarily a part of the cause. We
experience ball A hit ball B, but we never experience the reaction between A and B that
caused B to move. This shows that knowledge cannot go beyond experience.
According to Hume, Ball A moving and Ball B moving after Ball A hits B are observations.
But Ball B moving because of Ball A isn’t an observation; it’s an inference (technically,
an inductive inference). Therefore, according to Hume’s empiricism, we can’t
really know whether one ball caused the other ball to move! We only know for sure that
certain things happened, not whether they’re connected! Therefore, it’s impossible to know
whether any event causes another or whether they just occurred one after the other. In other
words, we can observe separate events, but we can never observe a causal link between them.
Hume goes on to say about cause and effect that “My intention then •••• is only to
make the reader more sensible of the truth of my hypothesis, that all our reasonings
concerning causes and effects are derived from nothing but custom; and that belief
is more properly an act of the sensitive than of the cogitative part of our nature.”
What is a custom or a habit? Every time we see a cause and effect repeating, it grows into our
customs and habits. For e.g., we put pencil to paper, and it leaves a mark, we do it again it leads
to a custom in our mind. We peel a banana and eat it, we do it again it forms a habit in our mind
that helps us eat it. Like ideas, we can create customs and habits by mixing experiences through
association. For e.g., a pen resembles a pencil, so you put it to paper and it also leaves a mark.
The idea of cause and effect is not something we see, it is something we infer based on constant
conjunctions of ideas. So we have no knowledge of cause and effect, only habits which make us
expect there to be causality.
While Hume understood that in practice the principle of cause and effect was robust enough
to rely on, as even he did, his argument made it clear that reason and logic aren’t everything.
In fact, taking it further, he showed how even his own philosophy could be doubted, and how
impossible it was to derive any sort of certainty about our conceptual knowledge.
He still stood by his empiricism, but the point was to illustrate how skepticism could poke
holes in anything, and how uncertain we really are about pretty much everything.
- Problem of induction
David Hume is the philosopher that is most often associated with induction. His formulation of the
problem of induction can be found in An Enquiry concerning Human Understanding. Here, Hume
introduces his famous distinction between "relations of ideas" and "matters of fact." Relations of
ideas are propositions which can be derived from deductive logic, which can be found in fields
such as geometry and algebra. Matters of fact, meanwhile, are not verified through the workings
of deductive logic but by experience. Specifically, matters of fact are established by making an
inference about causes and effects from repeatedly observed experience. While relations of
ideas are supported by reason alone, matters of fact must rely on the connection of a cause and
effect through experience. Causes of effects cannot be linked through a priori reasoning, but by
positing a "necessary connection" that depends on the "uniformity of nature."
While deductive logic allows one to arrive at a conclusion with certainty, inductive logic can only
provide a conclusion that is probably true.
The cornerstone of Hume's epistemology is the problem of induction. This may be the area of
Hume's thought where his scepticism about human powers of reason is most pronounced. [78] The
problem revolves around the plausibility of inductive reasoning, that is, reasoning from the
observed behaviour of objects to their behaviour when unobserved. As Hume wrote, induction
concerns how things behave when they go "beyond the present testimony of the senses, or the
records of our memory".[79] Hume argues that we tend to believe that things behave in a regular
manner, meaning that patterns in the behaviour of objects seem to persist into the future, and
throughout the unobserved present
Among Hume's conclusions regarding the problem of induction is that there is no certainty that
the future will resemble the past. Thus, as a simple instance posed by Hume, we cannot know
with certainty by inductive reasoning that the sun will rise tomorrow, but instead come to expect it
to do so because it has repeatedly done so in the past. Our minds can only operate on the
probability that an event will occur or repeat in the same way.
- External world
Hume concluded that such things as belief in an external world and belief in the existence of the
self were not rationally justifiable. According to Hume these beliefs were to be accepted
nonetheless because of their profound basis in instinct and custom.
The existence of things apart from our experience cannot be known, for we cannot compare our
experience with anything outside it as its supposed cause. Knowledge of the world, like
knowledge of causality, is based on habits
Hume states in his inquiry that - We have a natural impulse to have faith in their
senses and that, without reason, we suppose there is an external world, which is not
dependent upon our perceptions but would exist even though no sensible creatures
existed. But our senses alone cannot give us such knowledge of the external world.
Thus, he concludes that the senses are incapable of producing an opinion of the
continued existence of objects.
- Quranic verse
Islam rejects the notions of both, the idealists and the empiricists. Islam believes in the
existence of matter as well as of soul.
About senses and sense perceptions in Sura “The Bee” the Quran says; “it is He who
brought you out of your mother’s wombs when you did not know anything. He gave you
hearing, sight and intelligence and affections in the hope that you will be grateful.” (16:78).
The material universe is a reality. The Quran in Sura Adoration says; “Allah is the one who
created the heavens and the earth and all that is between them in six days.” (32:4). Then the
Quran testifies the creation and existence of soul in Sura “The Israelites” as such: “They ask
you concerning the soul, say: Soul is the special command of my Lord. You have been
given very little knowledge (about it).”(17:85).
As man is the blend of matter and soul, hence he/she attains knowledge through two
sources; material and spiritual. The Quran in Sura “The Prostration” says; “He who has
made everything which He has created Most Good; He began the creation of man with clay.
He made his offspring come into existence from an extract of insignificant fluid, then He gave
it proper shape and blew His spirit in it.: (32: 7-8).
God gave knowledge to Adam through inspiration; not through empiricism. In Sura “The
Heifer” the Quran says: “And He taught Adam the nature (names) of all things.”(2:31).
About the advancement of knowledge the Quran in Sura “Ta Ha” says: “Be not in haste with
the Quran before its revelation to you is completed, but say, “O my Lord! Advance me in
knowledge.” (20:114).
