John Locke is the founder of a new school of philosophy
called empiricism. He did it through a new interpretation of how we get
knowledge. The key concept of his empiricism is that everything we know we know
from experience. It was diametrically opposite to the Cartesian view that we
have our mind stuffed with ideas during our birth.
Builder of a new system
Locke built a new system of philosophy. In order to build
his new system Locke, at first, aims to clear the ground a little and remove
some of the rubbish that lies in the way to knowledge.The main rubbish that he
removes is the rubbish of the innate idea. Side by side Locke also describes
how our mind works and how much knowledge we can expect from our mind.
Start of empiricism
With the publication of his celebrated work An Essay
Concerning Human Understanding, Locke founded empiricism in
Britain.According to Locke our knowledge is restricted to ideas generated by
objects we experience. And ideas take two forms sensation and reflection.
Without exception all our ideas come through our senses and through reflection
upon these ideas our mind becomes internally aware of these ideas.
First of all we have to have the idea of sensation and then
that of reflection, because reflection means simply mind’s taking notice of its
own operations upon ideas, given through senses. Reflection involves
perception, thinking, doubting, believing, reasoning, knowing, willing
etc.Locke insists that each person’s mind is in the beginning like a blank sheet
of paper, void of all characters and the senses are the only agents to provide
the mind with ideas.
Simple and complex ideas
Locke divides ideas into two groups namely simple and
complex ideas. The source of ideas is experience. There are two kinds of
experiences namely internal and external. On the basis of these experiences our
ideas are also of two kinds: simple and complex ideas.
Simple means single idea. Whenever we look at an object
ideas come into our mind single file. Although an object has several ideas
blended together, the mind receives the ideas of those qualities separately
such as a white lily has the qualities of whiteness and sweetness without any
separation, but our mind can think of them separately, because each idea enters
through a different sense, namely the sense of sight and that of smell. But
different ideas may enter into our mind through the same sense, such as both
the ideas of hardness and coldness enter through the same sense namely the
sense of smell. Simple ideas constitute the chief source of the raw materials
out of which our knowledge is made. Simple ideas are received passively by our
mind through our senses. Simple ideas at first originate in sensation and then
by mind’s taking notice of its own operation originate in reflection.
Complex ideas occur when our mind puts together several
simple ideas and makes a composite idea out of simple ideas. Unlike simple
ideas, complex ideas are not received passively by our mind. Here the mind
actively receives the ideas. The mind does the three things such as the mind
joins ideas, brings them together, but holds them separate and abstracts. Thus
the mind joins the ideas of whiteness, hardness, and sweetness to form the
complex idea of a lump of sugar.
Primary and secondary qualities
To describe even more detail how we get our ideas Locke
turned his attention to the problem of
how ideas are related to the objects that produce them. In order to
account for how we get our ideas, Locke says that objects have qualities and he
defines a quality as the power to produce idea into our mind. Locke
distinguishes between two kinds of qualities namely primary and secondary
qualities.
Primary qualities are those qualities that really do exist
in the bodies themselves. Primary qualities resemble exactly those qualities
that inseparably belong to the object. A snowball, for example, looks round and
is round, appears to be moving and is moving.These qualities are primary
because they really exist in the object snowball. Primary qualities refer to solidity,
motion, or number.
Secondary qualities are those qualities that have no exact
counterpart in an object. We have the idea of cold when we touch the snowball
and the idea of white when we see it, but there is no whiteness or coldness in
it. Secondary qualities such as colors, tastes, sounds, odors, warmth, and
smells do not belong to or constitute bodies except as powers to produce these
ideas in us. What Locke wanted by this distinction is to distinguish between
appearance and reality.
Substance
The discussion of substance is an important part of Locke’s
theory of knowledge. He approached the problems from common sense point of
view. According to him as there are qualities so there must be something that
holds these qualities. If ,for example, we ask what has shape and color ,we
answer something solid and extended. Solidity and extension are the primary
qualities and if we ask in what they subsist, Locke answers substance. In
Locke’s philosophy substance is an abstract idea and he himself could not give
satisfactory definition of substance.
The degrees of knowledge
The extension and validity of our idea depend upon the
relations our ideas have to each other. Locke defines knowledge as nothing more
than the perception of the connection of an agreement or disagreement or
repugnancy of any of our ideas. There are three modes of perception namely
intuitive, demonstrative and sensitive and each one leads us to a different
degree of knowledge regarding reality.
Intuitive knowledge is the most
fundamental and certain. It leaves no room for doubt, hesitation and
examination. The mind perceives the agreement and disagreement of two ideas
immediately by themselves without the intervention of any other idea. We know
that a circle is not a square or that 6 is not 8, because we can perceive the
repugnancy of these ideas to each other. From intuitive knowledge we know that
we exit. Experience convinces us that we have intuitive knowledge of our own
existence.
Demonstrative knowledge occurs
when our minds perceive agreement and disagreement of ideas, not immediately,
but through other mediating ideas. We reach this knowledge through
investigation, reasoning, questioning and inquiry. Each step in demonstration
rests upon intuitive certainty. This type of knowledge leads our mind to an
exiting reality. By an intuitive certainty, man knows that out of nothing
nothing can be created. Since there are in fact existing things around us that
begin and perish in time, it is an evident demonstration that from eternity
there has been something. And Locke terms this eternal being which is most
knowing and most powerful as God.
Sensitive knowledge is not
knowledge in the strict sense of the term. It only passes under the name of
knowledge. So this sort of knowledge does not give us certainty, nor does it
extend very far. We have the knowledge of the existence of a particular man as
long as we observe him. But whenever the man moves away from us, we are no
longer assure of his existence. Nevertheless, sensitive knowledge gives us some
degree of knowledge but not certainty.
Thus, Locke founded empiricism in
Britain. Later his followers Berkeley and Hume led empiricism to further
development.