What is This Thing Called Science?
Chapter 1
Science as knowledge derived from the facts of experience.
- When it is claimed that science is special because it is based on the facts, the facts are presumed
to be claims about the world that can be directly established by a careful, unprejudiced use of
senses. Science is to be based on what we can see, hear and touch rather than on personal
opinions or speculative imaginings.
- Influential claim is that, as a matter of historical facts, modern science was born in the early
seventeenth century when the strategy of taking the facts of observation seriously as the basis for
science was first seriously adopted.
- Knowledge was based largely on authority, especially the authority of the
philosopher Aristotle and the authority of the Bible. It was only when this authority was challenge
by an appeal of experience, by pioneers of the new science such as Galileo, that modern science
became possible.
- It was an accepted axiom of Aristotle that the speed of falling bodies was regulated by their
respective weights.
- Until Galileo gave his denial and declared that weight had nothing to do with the matter, and that
two bodies of unequal weights would reach the ground at the same moment.
- Two schools of thought that attend to formalise a common view of science, that scientific knowledge
is derived from the fact, are the Empiricist and the Positivists.
British empiricist:
- John Locke
- George Berkeley
- David Hume
They held that all knowledge should be derived from ideas implanted in the mind by the
way of sense perception.
- The Positivists, had a broader and less psychologically oriented view of what facts amount to, but
shared the view o the empiricists that knowledge should be derived from the facts of experience.
- The Logical positivists were paying close attention to the logical form of the relationship between
scientific knowledge and the facts.
- Empiricists and Positivists shared the same view that scientific knowledge should in some way be
derived from the facts arrived at by observation.
There are two other distinct issues involved in the claim that science is derived from the facts:
- The nature of these ‘facts’ and how scientists are meant to have access to them.
- How the laws and theories that constitute our knowledge are derived from the facts once they have
been obtained.
Three components of the stand on the facts assumed to be the basis of science in the
common view can be distinguished:
1. Facts are directly given to careful, unprejudiced observers via the senses.
2. Facts are prior to and independent theory.
3. Facts constitute a firm and reliable foundation for scientific knowledge.
Seeing is believing
,Sight is the sense most extensively used to observe the world, and party for convenience.
The most important components of the human eye are the lens and the retina, the latter acting as a screen
on which images of objects external to the eye are formed by the lens.
1. Rays of light from a viewed object pass from the object to the lens via intervening medium.
2. These rays are refracted by the material of the lens in such way that they are brought to a focus on
the retina, so forming an image of the object.
3. Optic nerves pass from the retina to the central cortex of the brain. These carry information
concerning the light striking the various regions of the retina.
4. It is the re-coding of information by the brain that constitutes the seeing of the object by the human
observer.
Two points are strongly suggested the sense of sight that are incorporated into the
common or empiricists view of science.
- A human observer has more or less direct access to knowledge of some facts about the world
insofar as they are recorded by the brain in the cat of seeing.
- Two normal observers viewing the same object or scene from the same place will ‘see’ the same
thing.
Visual experiences not determine solely by the viewed object
Two normal observers viewing the same object from the same place under the same
physical circumstances do not necessarily have identical visual experiences, even
though the images on their respective retinas may be virtually identical.
What observers see, the subjective experience that they undergo, when viewing an
object or scene is not determined solely by the images on their retinas but depends also
on their experience, knowledge and expectations of the observer.
- The experiences and skilled observer does not have perceptual experiences identical to those of
the untrained novice when the two confront the same situation. This clashes with a literal
understanding of the claim that perceptions are given in a straightforward way via the senses. They
might see the same thing but interpret them differently.
- Regarding perception, the only things in which an observer has direct and immediate contact are his
or her experiences.
However, although the images in our retina form part of the cause of what we see,
another very important part of the cause is the inner state of our minds or brains, which
will itself depend on:
- cultural upbringing
- knowledge
- expectations
and will not be determined solely by the physical properties of our eyes and the scene
observed.
Under a wide variety of circumstances, what we see in various situations remains fairly
stable. The dependence of what we see on the state of our minds or brains is not so
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, sensitive as to make communications, and science, impossible.
Observable facts expressed as statements
- Fact: Statement that expressed the fact and it can also refer to the state of affairs referred to by
such statements.
It is necessary to distinguish statements of facts from the perceptions that might occasion the
acceptance of those statements as facts.
- Before, an observer can formulate and assent to an observation, he or she must be in possession of
the appropriate conceptual framework and knowledge of how to appropriately apply it. Because the
appropriate facts, formulated as statements, presuppose quite a lot of knowledge about the issue.
- Thus, the recording of observable facts require more than the reception, in the form of light rays,
that impinge on the eye. It requires the knowledge of the appropriate conceptual scheme and how
to apply it.
- Statements of facts are not determined in a straightforward way by sensual stimuli, and observation
statements presuppose knowledge, so it cannot be the case that we first establish the facts and
then derive our knowledge from them.
Why should facts precede theory?
Facts must be established prior to the derivation of scientific knowledge from them because:
- First establish facts and then build your theory to fit them. Both the fact that our perceptions
depends to some extent on our prior knowledge and hence on our state of preparedness and our
expectations and the fact that observation statements presuppose the appropriate conceptual
framework indicate that it is a demand that is impossible to live up to.
- Formulation of observation statements presuppose significant knowledge, and that the search for
relevant observable facts in science is guided by that knowledge.
- Neither acknowledge necessarily undermines the claim that knowledge has a factual basis
established by observations.
- The fact that the knowledge is necessary for the formulation of significant observation statements
still leaves open the question of which statements so formulated are born out by observation and
which are not.
- The idea that knowledge should be based on facts that are confirmed by observation is not
undetermined by the recognition that the formulation of the statements describing those facts are
knowledge-dependent.
The fallibility of observation statements
- The judgments of the truth or otherwise of an observation statement depends on the knowledge that
forms the background against which the judgment is made.
- Any view to the effect that scientific knowledge is based on the facts acquired by observation must
allow that the facts as well as the knowledge are fallible and subject to correction and that scientific
knowledge and the facts on which it might be said to be based are interdependent.
- Scientific knowledge has a special status in part because it is founded on a secure basis, solid facts
firmly established by observation.
2 difficulties:
- Perception are influenced by the background and expectations of the observer.
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