2.3C History & Methods of Psychology- 2021/2022 - Lecture 3 – Olive Lindemann – What is science - Nov 2021
What distinguishes psychology from everyday experiences/good science from non-science?
− Empiricist approach distinguishes science. You try to collect data/evidence to verify theories.
− Logical positivism (Vienna Circle) science proceeds best when it combines logical reasoning with empirical
observation to verify hypotheses.
Empirical Research Cycle: what a research process looks like:
1. Start with direct/unbiased observation that is theory free.
2. We can come up with a hypotheses, a single observation that we generalize to a general/empirical law that is
based on induction (general conclusion, principle, or explanation derived by reasoning from particular instances
or observations) e.g. all swans are white.
3. You try to explain empirical observations by developing a theory. This theory also enables you to deduce new
hypotheses (deduction) e.g. maybe go to other cities to look for swans to see if they really are all white.
4. Testing of the hypotheses based on new empirical material e.g. tests if our observation of white swans in other
cities are correct.
5. Evaluating the findings: predictions are tested through direct observation.
Karl Popper: we can never exclude there are other possibilities/influences. Science does not proceed by
induction (generalizations from observations). Science has to formulate theories and test them in diff situations
(deduction) = crucial step. We cannot test a theory once: we have to generalize and test theory in diff situations. The
theory has to be formulated in a way it can be proven wrong (only way to make a theory scientific). A scientific theory
has to predict an outcome that can be empirically tested and falsifiable e.g. ‘swans are sometimes white or sometimes
black’, is not a scientific theory because it can’t be tested or falsified.
The empirical content of a theory increases with the degree of falsifiability. We can only make scientific progress by
falsifying a theory. A theory that explains everything explains nothing e.g. if all the swans I observe are white, my theory
is proven, but at the same time it can be falsified because there could be a black swan in a country I don’t know of. We
can never exclude better explanations than ours, or better theories than ours.
If theory is falsified: we have made scientific progress and have to modify our theory/ explanation that we have to falsify
again. The circle goes on and on.
Thomas Kuhn: Science is not a process that continuously processes new knowledge → there’s waves. If you
look how science really takes place, there’s not much process over time, until the point there are new observations made
that the older theories can’t explain → new theories have to be made that aren’t part of old theories.
Diff than Popper; Kuhn observed the process of science in practice. Popper is saying ‘science should be like this’ and Kuhn
says: ‘but science is usually this in practice’.
Empirical science is based on some general assumptions (Hughes):
Determinism: all events have cause and nothing Parsimony: the simplest explanation should be preferred.
happens without a cause. We might not be able to Two theories explaining the same phenomenon, the better
observe or know the cause, but there’s always a theory is the simplest one. People find it more scientific if it’s
cause. There’s nothing from the future that can complicated, however; it should be as straightforward and
influence the past. parsimonious as possible.
Scepticism: nothing is written in stone, nothing is Falsification: science should try to falsify theories by ‘testing’
accepted as complete truth. Question and investigate or challenging them.
any assertion and claim. Accepting claims on the basis
of authority is unscientific.
What distinguishes psychology from everyday experiences/good science from non-science?
− Empiricist approach distinguishes science. You try to collect data/evidence to verify theories.
− Logical positivism (Vienna Circle) science proceeds best when it combines logical reasoning with empirical
observation to verify hypotheses.
Empirical Research Cycle: what a research process looks like:
1. Start with direct/unbiased observation that is theory free.
2. We can come up with a hypotheses, a single observation that we generalize to a general/empirical law that is
based on induction (general conclusion, principle, or explanation derived by reasoning from particular instances
or observations) e.g. all swans are white.
3. You try to explain empirical observations by developing a theory. This theory also enables you to deduce new
hypotheses (deduction) e.g. maybe go to other cities to look for swans to see if they really are all white.
4. Testing of the hypotheses based on new empirical material e.g. tests if our observation of white swans in other
cities are correct.
5. Evaluating the findings: predictions are tested through direct observation.
Karl Popper: we can never exclude there are other possibilities/influences. Science does not proceed by
induction (generalizations from observations). Science has to formulate theories and test them in diff situations
(deduction) = crucial step. We cannot test a theory once: we have to generalize and test theory in diff situations. The
theory has to be formulated in a way it can be proven wrong (only way to make a theory scientific). A scientific theory
has to predict an outcome that can be empirically tested and falsifiable e.g. ‘swans are sometimes white or sometimes
black’, is not a scientific theory because it can’t be tested or falsified.
The empirical content of a theory increases with the degree of falsifiability. We can only make scientific progress by
falsifying a theory. A theory that explains everything explains nothing e.g. if all the swans I observe are white, my theory
is proven, but at the same time it can be falsified because there could be a black swan in a country I don’t know of. We
can never exclude better explanations than ours, or better theories than ours.
If theory is falsified: we have made scientific progress and have to modify our theory/ explanation that we have to falsify
again. The circle goes on and on.
Thomas Kuhn: Science is not a process that continuously processes new knowledge → there’s waves. If you
look how science really takes place, there’s not much process over time, until the point there are new observations made
that the older theories can’t explain → new theories have to be made that aren’t part of old theories.
Diff than Popper; Kuhn observed the process of science in practice. Popper is saying ‘science should be like this’ and Kuhn
says: ‘but science is usually this in practice’.
Empirical science is based on some general assumptions (Hughes):
Determinism: all events have cause and nothing Parsimony: the simplest explanation should be preferred.
happens without a cause. We might not be able to Two theories explaining the same phenomenon, the better
observe or know the cause, but there’s always a theory is the simplest one. People find it more scientific if it’s
cause. There’s nothing from the future that can complicated, however; it should be as straightforward and
influence the past. parsimonious as possible.
Scepticism: nothing is written in stone, nothing is Falsification: science should try to falsify theories by ‘testing’
accepted as complete truth. Question and investigate or challenging them.
any assertion and claim. Accepting claims on the basis
of authority is unscientific.
