04/12/23 1

Theory of Falsificationand its evolution

04/12/23 2

Domain of this talk

Epistemology:

Branch of philosophy concerned with the nature and scope of knowledge

Ontology : Study of conceptions of reality and the nature of being

Is science based on faith? What is the scientific method? How are new discoveries treated? Is everything reducible to physics and

mathematics? Is everything reducible to a few rules?

Philosophy of Science

04/12/23 3

The Middle Ages

5th century -16th century Medieval and Dark Ages

Saint Augustine

Islamic al-Andalus passed much of this on to Europe The replacement of Roman numerals with the decimal positional number system and the invention of algebra allowed more advanced mathematics.

First Crusade 1095-1099Second Crusade 1147–1149116 years of war from 1337 – 1453 Between France & England

Islamic Golden Age

04/12/23 4

Heliocentrism & ChurchWestern Christian biblical references: Psalm 93:1, Psalm 96:10, and 1 Chronicles 16:30 include text stating that

"the world is firmly established, it cannot be moved." In the same tradition, Psalm 104:5 says,

"the LORD set the earth on its foundations; it can never be moved.“Further, Ecclesiastes 1:5 states that

"And the sun rises and sets and returns to its place, etc."[74]

Galileo (1564 – 1642)

Thomas Aikenhead (c. 1678 - 8 January 1697) was a Scottish student from Edinburgh, who was prosecuted and executed on a charge of blasphemy

04/12/23 5

Logical Induction

Induction is dominant mode of inquiry Truth observed through empirical study and

experimentation Rational and unbiased examination of

nature

Observation Repetition Induction(1)

Hypothesis Deduction or generalization

Consequence or prediction

Testing Induction(2)

Bacon (1561-1626)

04/12/23 6

Laws of motion

Sir Isaac Newton (1643 – 1727)

"Gravity explains the motions of the planets, but it cannot explain who set the planets in motion. God governs all things and knows all that is or can be done."[17]

Newton may have rejected the church's doctrine of the Trinity.

Newton refashioned the world governed by an interventionist God into a world crafted by a God that designs along rational and universal principles.[24] These principles were available for all people to discover, allowed people to pursue their own aims fruitfully in this life, not the next, and to perfect themselves with their own rational powers.[25]

04/12/23 7

Epistemology

Knowledge is justified true belief

The justification for the belief must be infallible.

The Gettier problem

Specific theories of knowledge acquisition:1. Empiricism : all hypotheses and theories must be tested against

observations of the natural world, rather than resting solely on a priori reasoning

, intuition, or revelation.

2. Rationalism : knowledge is primarily acquired by intuition. Any view appealing to reason as a source of knowledge or justification

3. Constructivism : scientific knowledge is constructed by scientist and not discover from the world through strict scientific method

04/12/23 8

18th Century EpistemologistRationalism

Descartes Spinoza

Leibniz

Empiricism

Locke Berkeley

Hume

Wolff

Kant

It is our ideas which give form to reality, not reality whichgives form to our ideas.

04/12/23 9

All A observed so far are B.   [i.e. All A are B]

X is an A not yet observed.     [i.e. X is not an A]

Therefore X is B.       [X is B.]

What does it take to confirm a universal generalization?

Logical Problem of Induction

Deductive logic (drastically oversimplified):All A are B. X is an A. Therefore X is B.

Inductive logicAll copper we have tested conducts electricity. X is a piece of copper yet to be tested. Therefore X will conduct electricity.

04/12/23 10

Logical Positivism

Vienna Circle included Rudolf Carnap, Otto Neurath, Viktor Kraft, Hans Hahn, and Herbert Feigl.

The principal objective of the members of the Circle was to unify the sciences, which carried with it, in their view, the need to eliminate metaphysics once and for all by showing that metaphysical propositions are meaningless.

Rudolf Carnap (1891-1970) Bertrand Russell (1872–1970) Ludwig Wittgenstein (1889 –1951)

Tractatus Logico-Philosophicus

04/12/23 11

Goodman’s Riddle:Grue and Bleen

When there is more than one inductive conclusion that is consistent with our observations, which one should we chose?

Henry Nelson Goodman (1906-1998)

Grue: Observed before or at t and green or observed after t and blue. Let t be midnight, Decmber 31 2009. Then all observed emeralds are grue / green. Should we infer by simple induction that all emeralds are grue or green?

Bleen: X is examined before the year 2000 and found to be blue, or X is not examined until after the year 2000 and found to be greenGreen: X is green if examined before the year 2000 and found to be grue, or X is not examined until after the year 2000 and found to be bleen.

04/12/23 12

The Falsification Thesis

Sir Karl Raimund Popper (1902 –1994)

Murderer of Freud and Marx Ideas Problem with Darwinian Evolution

Charles Robert Darwin (1809 –1882) Karl Heinrich Marx (1818 –1883) Sigismund Freud (1856 –1939)

He published his first book, Logik der Forschung (The Logic of Scientific Discovery), in 1934. Here, he criticised psychologism, naturalism, inductionism, and logical positivism, and put forth his theory of potential falsifiability as the criterion demarcating science from non-science.

Scientific theories are never truly verified. Moreover, to be always verified is not a virtue in a scientific theoryVerification and falsification are asymmetrical: No accumulation of confirming instances is sufficient to verify a universal generalization. But only one disconfirming instance suffices to refute a universal generalization. Scientific theories are distinguished by the fact that they are capable of being refuted. They are falsifiable.

you can never justify any scientific theory, but you can falsify it

04/12/23 13

Einstein’s General Relativity: If it had failed its famous test of 1919, no one would have taken it seriously.

But it passed the test, and Newton’s theory of gravitation was refuted.

Albert Einstein (1879-1955)

Light from a star passing near the Sun should be deflected. The evidence is the displacement of the star’s apparent position.

Empirical Test of General Relativity

04/12/23 14

Falsification of Darwinian Evolution

Richard Dawkins said that "If there were a single hippo or rabbit in the Precambrian, that would completely blow evolution out of the water. None have ever been found.

Human DNA should be more similar to great apes than other mammals. If this is not the case, then common descent is falsified.

Popper said that natural selection "is not a testable scientific theory but a metaphysical research program".

However, Popper later said "I have changed my mind about the testability and logical status of the theory of natural selection, and I am glad to have the opportunity to make a recantation."

"Darwin's own most important contribution to the theory of evolution, his theory of natural selection, is difficult to test." However, "[t]here are some tests, even some experimental tests; and in some cases, such as the famous phenomenon known as 'industrial melanism', we can observe natural selection happening under our very eyes, as it were. Nevertheless, really severe tests of the theory of natural selection are hard to come by, much more so than tests of otherwise comparable theories in physics or chemistry."

The model of cultural evolution known as memetics is as of yet unfalsifiable

04/12/23 15

Popperian Cosmology

World 1: the world of physical objects and events, including biological entities World 2: the world of mental objects and events World 3: the world of the products of the human mind

04/12/23 16

Critical Rationalism

Critical Rationalism is the acceptance of human fallibility

Critical Rationalism: Scientific theories, and any other claims to knowledge, can and should be rationally criticized, and (if they have empirical content) can and should be subjected to tests which may falsify them. Fallibilism

Evolutionary Epistemology

Brian Skyrms

The mere fact that a theory has survived the most rigorous empirical tests available does not, in the calculus of probability, predict its ability to survive future testing

Evolutionary epistemologists argue that units of knowledge themselves, particularly scientific theories, evolve according to selection

04/12/23 17

Is it really falsifiable

Newtonian Gravitation Theory: Predicts that every acceleration of every body can be traced to an interaction with some other body, according to their masses and the distance between them.

F Gm1m2

r2

What to do when we observe an acceleration that has no visible source? Is the theory refuted?

No: The theory demands that the missing mass be found.

Max Planck in his Scientific Autobiography and Other Papers, stated "A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die and a new generation grows up that is familiar with it."

This view contradicts that forwarded by Karl Popper

04/12/23 18

Duhem-Quine Thesis

In the first half of the 19th century, astronomers were observing the path of the planet Uranus to see if it conformed to the path predicted by Newton's law of gravitation;

It didn't. Possible Explanations: Telescopic observations were wrong because of some unknown factor Newton's laws were in error God was causing the perturbation in order to show the hubris of modern

science

Eventually accepted that an unknown planet (Neptune) was affecting the path of UranusTheory-Laden: interpretation of observation is dependent on theory

Dark Matter

Pierre Duhem (1861 – 1916)

underdetermination of theories

04/12/23 19

Reductionism Complex system is nothing

but the sum of its parts

Daniel Dennett

Descartes argued the world was like a machine, its pieces like clockwork mechanisms, and that the machine could be understood by taking its pieces apart, studying them, and then putting them back together to see the larger picture.

Steven Arthur Pinker

behavioral sciences should become "genuine" scientific disciplines by being based on genetic biology, and on the systematic study of culture (cf. Dawkins's concept of memes)

04/12/23 20

Thomas Kuhn on Scientific Revolutions (cf. The Structure of Scientific Revolutions, 1962.)

Kuhn argues that scientific advancement is not evolutionary, but rather is a "series of peaceful interludes punctuated by intellectually violent revolutions", and in those revolutions "one conceptual world view is replaced by another".

Paradigm: Kuhn’s idea that a scientific theory is not just a set of theoretical principles. It is an entire world-view

Examples of paradigm shifts in science The transition from a Ptolemaic cosmology to a Copernican one. The unification of classical physics by Newton into a coherent mechanical worldview. The transition between the Maxwellian Electromagnetic worldview and the Einsteinian Relativistic worldview. The transition between the worldview of Newtonian physics and the Einsteinian Relativistic worldview. The development of Quantum mechanics, which overthrew classical mechanics. The development of Darwin's theory of evolution by natural selection, which overturned Lamarckian theories of evolution by inheritance of acquired characteristics. The acceptance of Plate tectonics as the explanation for large-scale geologic changes.

Paradigm Shifts

04/12/23 21

Multiple Realizability

Hilary Whitehall Putnam

Contrary to the famous claim of type-identity theory, it was not true that "pain is identical to C-fibre firing."

Against Type-Identity

functional isomorphism = "Two systems are functionally isomorphic if there is a correspondence between the states of one and the states of the other that preserves functional relations."

Functionalism is a theory of the mind in contemporary philosophy, developed largely as an alternative to both the identity theory of mind and behaviorism. Its core idea is that mental states (beliefs, desires, being in pain, etc.) are constituted solely by their functional role — that is, their causal relations to other mental states, sensory inputs, and behavioral outputs.

04/12/23 22

Walking along one day on the newly-discovered coast of Australia, Captain Cook saw an extraordinary animal leaping through the bush.

   "What's that?" he asked one of the aborigines accompanying him.

   "Uh - gangurru." he replied - or something like that. Captain Cook duly noted down the name of the peculiar beast as 'Kangaroo'.

Some time later, Cook had the opportunity to compare notes with Captain King, and mentioned the kangaroo.

   "No, no, Cook", said King, "the word for that animal is 'meenuah' - I've checked it carefully.

   "So what does 'kangaroo' mean?"

"Well, I think," said King "it probably means something like 'I don't know'...”

I don’t knowSource:Source: http://www.consciousentities.com/gavagai.htm

Imagine you come across a new tribe in the Brazilian jungle, and the task is to interpret their language: to find out word-meanings and rules of grammar.

This situation is entirely different from second-language learning. There are no familiar-sounding words, no teacher who speaks both languages, etc.

Radical Translation / Indeterminacy of Translation

04/12/23 23

Two Dogmas of Empiricism

"a statement is analytic if it is true by virtue of meanings and independent of fact"

No unmarried man is married (true by definition ) No bachelor is married. (transformed into logical truths by substituting

synonyms) Necessarily all and only bachelors are unmarried men

Analyticity and Circularity

Quine’s Holism

Quantum Logic

Duhem–Quine Thesis

Cats are animals

evidence confirms or disconfirms not just a specific hypothesis, but a

whole theory

we do not, or should not, regard any sentence as "immune from revision," since there may be circumstances in which the best way to revise our overall theory is to give up some sentence which had previously seemed unshakeable--even "definitions."

1. Belief in an analytic/synthetic distinction2. Reductionism (every meaningful statement is equivalent to a statement about experience)

04/12/23 24

Math

Holism

logic

The totality of our so-called knowledge or beliefs ... is a man-made fabric which impinges on experience only along the edges ... A conflict with experience at the periphery occasions readjustments in the interior of the field ... But the total field is so undetermined by its boundary conditions, experience, that there is much latitude of choice as to what statements to re-evaluate in the light of any single contrary experience ... If this view is right, it is misleading to speak of the empirical content of an individual statement ...

04/12/23 25

Claims (Lessons) from this talk

Truth is almost unattainable Theory of Meaning and linguistic plays an

important role in our knowledge Metaphysics as part of our knowledge is

interconnected with other branches of knowledge and therefore is (not) falsifiable

Depending on your lifestyle philosophy can have pragmatic consequences for you