lecture 9 / 10 + chapter 9 Flashcards
wittgenstein
Most influential philosopher in 20th century. There is wittgenstein 1 and 2 with two very different views
logical positivist
a group in vienna against traditional vague philosophy to make it scientific.
the linguistic turn
philosophy is given a new purpose: clarification fo language and assessment of which sentences are meaningful
positivism
scientific knowledge based on empirical evidence. rejects metaphysics (ideele werkelijkheid)
logical positivism (/empiricism)
experiences are gained through sensory perception: sense data. philos should stop thinking about metaphysics and instead understand the essence of scientific approach. central theme: verification principle
manifesto of logical positivism
- meaningful claims are either empirical or logical in nature
- Logical claims are verifiable by looking at their form and help represent the world
- Empirical claims are about the world and can be verified by observation
- Only claims that are verifiable are meaningful
verification criterion
- If you cant find out the truth of a sentence by looking at reality, then the sentence is meaningless: the soul is immortal.
- meaningful sentence: there are 350 people in this room
- using verifiability to demarcate science
verifiability and sense data
logical positivist make strict separation between observation and theory. Think about the structure of science picture
problems verifiablity
- separation of theory and observation.
- theory ladenness
- underdetermination of theory by data
- induction
- unobservable entities
separation of theory and observation. (problem verification)
observational vocab (mass is 100 kg) is attached to theoretical vocab (meaning of mass) through correpsondence rules. The meaning of mass is not reducible to observations. theoretical statements are richer than observational statements
theory ladenness
observations are neutral according to LP. But there is a lot of theory and assumptions in it. But big difference between observing x and observing that x has property y. The latter type of observation is important but relies on a theory that defines property y. Also, observations are based on instruments and their accuracy is based on theory. So observation and theory are not so separated. Example: with fMRI scan you say ‘ I see a lot of brain activity’, but you actually see a black/white picture with dark and white parts.
Underdetermination of theory by data
For same data, multiple theories. To choose between theories, scientists use other criteria but those criteria are theoretical as well.
induction (problem verification)
General statements are not verifiable (like f = m x a). With the verification criterion, causal relationship cant be part of science, because it is induction.
why does LP fail
- separation of theory and observation.
- theory ladenness
- underdetermination of theory by data
- induction
- unobservable entities
unobservable entities (problem verification)
Statements about unobservable entities such as microbes are neither verifiable nor reducible to observations.
wittgenstein 1
tractatus logico philosophica: de wereld bestaat uit feiten. alles moet logisch zijn. waarover men niet spreken kan, daarover moet men zwijgen. doel: begrijpen hoe taal de werkelijkheid spiegelt. taal heeft vaste structuur. meaningful statements depicts possible states of affairs, but can be either true or false. Starting point of logical positivism.
wittgenstein 2
taal is geen statisch systeem maar veel flexibler. taal heeft verschillende functies aghankelijk van de context (een regel, een vraag, een grap). begrip van woord afhankelijk van situatie. Opposing the view of logical positivist.
the sayabel
proposities (uitspraken) die een logische structuur hebben en iets over de werkelijkheid zeggen. Ze beschrijven feiten van de wereld.
the unsayable
alles wat buiten logische en feitelijke uitspraken valt. bijvoorbeeld ethiek. dit kan niet geverifieerd worden
einstein inspo voor popper
einsteins theory is wrong, because prediction didnt come true so he changes theory. popper: strong theory because it cant explain everything –> essence of science. (adler and freud could explain everything with their theory and that was the weakness). The more precise, the more informative
falsificationism (popper)
- theories’ predictions can be tested against observations
- theory free observation is impossible
- induction is impossible: you cant induce theories from observations. THus deduction.
- doesnt matter where theories come from
hypothetico-deductive model
theory, hypothese, testen, falsify theory or corroboration
corroboration
It means the theory is not falsified because the predictions came true. however, it is not verified. theory can still be falsified.
context of discovery (falsificationism)
Het maakt niet uit hoe men aan een theorie komt (als het maar falsifiable is)
context of justification (falsificationism)
een theorie is gerechtvaardigd als het openstaat voor weerlegging en empirische toetsing
why is falsificationism rationalism
It is rationalism because theories come from our mind, but those theories are tested, hence critical rationalism.
Demarcation criterion
distinguishes science from pseudoscience. Such as verification and falsification criterion.
Falsification criterion
- Statements or theories are scientific only if they are in conflict with possible observations.
- A theory must be falsifiable
- A more precise and general theory excludes more. Precise = making precise predictions. general = less conditional, more general)
philosophy of science
a branch of filo that studies the foundations of scientific research
wat lost popper op met falsification
inductie probleem,
problems falsification
- no distinction between better or less supported theories
- all knowledge is hypothetical and can never be established : popper
- hard falisification is difficult
duhem-quine thesis
If a prediction doesn’t come true it could be because of the theory, or due to wrong measurements, wrong tests. A theory is never in isolation.
ad hoc modifications
modifications to a theory that according to popper make the theory less falsifiable and decrease the scientific value.
Thomas kuhn
there are no rules for something to be science or not. there are paradigm shifts. example: the meaning of the word time has changed. There is no progress in science, only changes of theories.
stages of science
- Pre science: chaotic collection of facts, observations and models. no agreement.
- Normal science 1: general framework
- Anomalies and crisis: too many anomalies, open to alternatives
- Revolution: paradigm shift
- Normal science 2
degenerative research program (revolution)
paradigm that doesnt allow new predictions and increaisng ad hoc modifications
progressive research program
paradigm that allows new predictions that can be tested
science wars
debate between scientists and postmodernists. postmodernists: ‘science is a social construction; it isnt objective but a story told by a particular community on the basis of ist language and culture’
epistemological anarchism
Feyeraben is against methods, galileo would not have been scientific because he didnt follow the methods (he prooved heliocentric model).
lakatos
- student of popper
- tries to save rationality from kuhn’s relativism and feyerabend anarchism.
- sophisticated falsificationism
sophisticated falsificationism.
Lakatos combines normative elements of popper’s philosophy and descriptive elements of Kuhn’s philosophy. direct falsification is rare: Theories won’t be directly thrown away if falsified, but wait for a better alternative.
lakatos research programs
Progressive programs: growth, new techniques and facts. Degenerative programs: shrinkage, no new techniques and facts. Normative component: a rational scientist should stick with a progressive programme but abandon a degenerative programme.
