Presentation is loading. Please wait.

Presentation is loading. Please wait.

Rationalism –v- Empiricism From where does knowledge come? MRes Philosophy of Knowledge: Day 2 - Session 2 (slides available at

Similar presentations


Presentation on theme: "Rationalism –v- Empiricism From where does knowledge come? MRes Philosophy of Knowledge: Day 2 - Session 2 (slides available at"— Presentation transcript:

1 Rationalism –v- Empiricism From where does knowledge come? MRes Philosophy of Knowledge: Day 2 - Session 2 (slides available at http://cfpm.org/mres)

2 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-2http://cfpm.org/mres Part 1: Some Key Ideas

3 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-3http://cfpm.org/mres A picture of reasoning we get from Ancient Greece Reasoning is (largely) a public activity involving rhetoric and debate An effort to distinguish (and exclude) bad arguments (e.g. identifying “fallacies”) Good argument results in good decisions Argument seen to lead from known (i.e. agreed) truths to conclusions… …which may be new or used to show other beliefs are wrong (or inconsistent)

4 Rationalism –v- Empiricism. MMUBS Mres Epistemology, session 2, http://cfpm.org/~bruce slide-4 This activity is abstracted to “Reason” and “Rationality” These are ideals –Not necessarily what people actually do –They acquire a normative flavour Major questions are then: –What is the role of Reason (as opposed to perception, action etc.) in particular as to its relation to knowledge? –What is Rational (in contrast to irrational)? Can be seen as a search to escape the contingencies and particularities of the observed world… …to more general/fundamental/etc. truth

5 Rationalism –v- Empiricism. MMUBS Mres Epistemology, session 2, http://cfpm.org/~bruce slide-5 The necessary – contingent distinction Necessary truths –Statements that have to be true –For some reason it is not possible that they could be false –e.g. Sentient beings exist Contingent truths –Statements that just happen to be true –If things were different they might not have been true –E.g. The UK has a Reigning monarch

6 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-6http://cfpm.org/mres The analytic – synthetic distinction Analytic truths –True by definition or deduction –Are necessary –Abound in mathematics or logic –e.g. All bachelors are unmarried Synthetic truths –True of the world –Are contingent –Abound in natural sciences –e.g. The Earth orbits the Sun

7 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-7http://cfpm.org/mres The a priori – a posterior distinction a priori knowledge –What one knows before taking into account observations or evidence –May include necessary/analytic truths, assumptions, given facts, etc. a posterior knowledge –What one knows after taking into account observations and evidence –May include laws and explanations of natural or social phenomena

8 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-8http://cfpm.org/mres The induction – deduction distinction Deduction –Finding the necessary consequences of other propositions –An analytic “unfolding” of what is already known –Produces a new form of old knowledge –If we know A and A  B then we can deduce B –e.g. Working out that not everybody voted Induction –Finding new generalisations from evidence (facts) –A learning process –Results in new knowledge –S 1 was W, S 2 was W, S 3 was W, …. All S i are W –e.g. Discovering that racism is increasing

9 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-9http://cfpm.org/mres The context of discovery – context of justification distinction The context of discovery: –The situation/context where an item of knowledge is discovered or hypothesised –When and how knowledge is learnt The context of justification: –The situation/context where the knowledge is justified, established or verified –When and how knowledge is established as reliable e.g. Fleming discovered penicillin when he accidentally let a culture be contaminated by mould but … it was justified as knowledge as the result of further experiment and observation by many

10 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-10http://cfpm.org/mres The Idea of Causation One event (A) causes another (B) if B always follows A A is necessary to B occurring And (generally) there is some mechanism connecting A to B E.g Does smoking cause Cancer Event AEvent B

11 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-11http://cfpm.org/mres Descartes’ Two Ways to Truth: from the general to the particular “There are and can be only two ways of searching into and discovering truth. The one flies from the senses and particulars to the most general axioms, and from these principles, the truth of which it takes for settled and immovable, proceeds to judgement and the discovery of middle axioms. And this way is now in fashion. … ReasonGeneral Principles Specific Truths Contingent facts and observations

12 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-12http://cfpm.org/mres Descartes’ Two Ways to Truth: from the particular to the general …The other derives axioms from the senses and particulars, rising by a gradual and unbroken ascent, so that it arrives at the most general axioms last of all. This is the true way, but as yet untried." Francis Bacon (1620), First Book of Aphorisms General Principles Contingent facts and observations Specific Truths etc… Reason

13 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-13http://cfpm.org/mres Rationalism Knowledge arises from reasoning Is the position that the way to knowledge is from the general to the particular Requires some general a priori truths which it views as necessary (usually) Characterised by deduction The general principles gives meaning to the observations by relating them E.g. Descartes’ “I think therefore I am”

14 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-14http://cfpm.org/mres Empiricism Knowledge arises from observation Is the position that the way to knowledge is from the particular to the general Requires some particular a posterior truths (perceptions) which are contingent Characterised by induction The general principles arise from the process of relating observations E.g. Galileo’s “All truths are easy to understand once they are discovered; the point is to discover them”

15 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-15http://cfpm.org/mres Part 2: An Example – Rational Choice Theory

16 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-16http://cfpm.org/mres Basic Idea of Rational Choice Theory Humans are (imperfectly) rational That is, their behaviour can be explained (modelled) by assuming they are basically rational at least as a starting point The conception of rationality here is a generalisation of economic rationality (constrained optimisation) E.g. Smith’s “invisible hand” balancing supply and demand via price changes

17 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-17http://cfpm.org/mres Principles of Rational Choice Theory Resourceful: man can search for and find possibilities, he can learn and be inventive; Restricted: man is confronted with scarcity and must substitute (choose); Expecting: man attaches subjective probabilities to (future) events; Evaluating: man has ordered preferences and evaluates (future) events; Maximizing: man maximizes (expected) utility when choosing a course of action

18 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-18http://cfpm.org/mres Example: please assess What evidence is presented? What kinds of evidence does he use? What are the a priori assumptions used? What is the nature of the rationality that the author presents? What does his argument show? Do you find it convincing? How would you argue against this? How could he be shown to be wrong?

19 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-19http://cfpm.org/mres The Example: more issues Is the author a Rationalist or an Empiricist? Does the author rely on a priori truths or a postiori evidence? Is the author claiming his arguments are necessarily true or only contingently true? Has the author go to his conclusions using deduction or induction?

20 Rationalism –v- Empiricism. MMUBS Mres Epistemology, session 2, http://cfpm.org/~bruce slide-20 Part 3: A brief account of some of the arguments

21 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-21http://cfpm.org/mres Recap of Induction Supposed structure: –The 1 st swan is white –The 2 nd swan is white –… etc. –Therefore all swans are white Relies on there being observable patterns Produces (fallible) generalisations A source for hypotheses and theories A natural thing to do

22 Rationalism –v- Empiricism. MMUBS Mres Epistemology, session 2, http://cfpm.org/~bruce slide-22 The Problem of Induction Hume (17-??) A Treatise Concerning Human Understanding Although one does repeatedly observe a particular conjunction (or sequence) of events… …this never guarantees that this will always be the case. Thus there are no causal laws

23 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-23http://cfpm.org/mres The Inductive Justification of Induction The argument –Induction worked in case 1 –Induction worked in case 2 –… etc. … –Therefore induction works in all such cases A self-referring and self-justifying argument But if it is false it does not justify itself Is it supported by the evidence? What is the scope of the cases?

24 Rationalism –v- Empiricism. MMUBS Mres Epistemology, session 2, http://cfpm.org/~bruce slide-24 Some difficult questions about induction What are these facts? –Are they states of the world? –Are they statements in language? –Are they something else (propositions)? How do we select these facts? Why did we look for these facts? What conceptual framework did we use to construct our generalisations about them? What background assumptions are there common to all these facts?

25 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-25http://cfpm.org/mres Popper’s Falsificationism Induction never proves anything Hypotheses can only be disproved by observing a counter-example (a black swan) We rely on hypotheses more as they survive attempts to disprove them If there is constant innovation of hypotheses and attempts to disprove them then knowledge will progress Hypotheses that are not amenable to being falsified (unfalsifiable hypotheses) are dubious

26 Rationalism –v- Empiricism. MMUBS Mres Epistemology, session 2, http://cfpm.org/~bruce slide-26 Comments on Popper’s Falsificationism History of science does not fully support it (e.g. Michelson-Morley experiment) How does one know whether the counter- example shows the main hypothesis is wrong or merely an auxiliary assumption? Marks a switch from the context of discovery to the context of justification Results in an evolutionary picture of the development of knowledge (evolutionary epistemology)

27 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-27http://cfpm.org/mres Lakatos’ Core and Protective Belt Research programs as key entities –These have a core of fundamental frameworks, methods and assumptions that characterises them –And a belt of less fundamental hypotheses, observations, techniques In the face of counter-examples research programs change things in the belt and preserve the core Some programs are more successful than others (the “degenerate programs”)

28 Rationalism –v- Empiricism. MMUBS Mres Epistemology, session 2, http://cfpm.org/~bruce slide-28 In the Social Sciences One is usually dealing with meaningful behaviour Meaning is (almost always) an a priori given but not always agreed upon The context (or scope) of the induction or falsification is of great importance Falsification is difficult since it is easy to adjust the belt to protect any hypotheses Coherency with other thought often as important (to academics) as evidence

29 Rationalism –v- Empiricism. MMUBS Mres Epistemology, Day 2 – seesion 1, http://cfpm.org/mres slide-29http://cfpm.org/mres Summary of Session Both reason and evidence are needed for good generalisations about the world But how these are combined is important Care and awareness are needed with any a priori assumptions and frameworks… …although ultimately these are unavoidable Key decisions are what to do if some evidence seems to conflict with a hypothesis – beware!

30 Rationalism –v- Empiricism. MMUBS Mres Epistemology, session 2, http://cfpm.org/~bruce slide-30 The End Experiment escorts us last - His pungent company Will not allow an Axiom An Opportunity Emily Dickinson (1830-1886) (as usual slides etc. at: http://cfpm.org/mres)


Download ppt "Rationalism –v- Empiricism From where does knowledge come? MRes Philosophy of Knowledge: Day 2 - Session 2 (slides available at"

Similar presentations


Ads by Google