PSY1SFP Scientific Foundations of Psychology Lecture 1 PDF

PSY1SFP: Scientific Foundations of Psychology Dr Annukka Lindell [email protected] Office hours: Mondays 2-3pm Lecture 1 : What is psychology? Lecture Plan What is philosophy? Philosophical assumptions underlying psychology How we can know anything? Descartes and dualism What is science? Indu...

PSY1SFP: Scientific Foundations of Psychology Dr Annukka Lindell [email protected] Office hours: Mondays 2-3pm Lecture 1 : What is psychology? Lecture Plan What is philosophy? Philosophical assumptions underlying psychology How we can know anything? Descartes and dualism What is science? Induction, falsification & deduction The Scientific Method Does psychology fulfil the criteria? What is Philosophy? ‘Philosophy’ comes from the Greek philosophia: love of wisdom Philosophy is the study of knowledge, reality and existence Philosophy is alive and well, with (often) hidden philosophical assumptions providing the framework for psychological theories What is Philosophy? We all have a philosophy (Jaspers, 1954), though often a) people don’t know they have a philosophy and/or b) find it hard to explain their philosophical assumptions Philosophical assumptions are the ideas behind the ideas (i.e., the things that are logically necessary for an idea to be valid; Silfe & Woolery, 2006) Philosophical Assumptions in Psychology There are many philosophical assumptions underlying psychology Empiricism: conclusions must be based on observation (objective, systematic, replicable) Measureablity: to study something we must be able to measure/quantify it Philosophical Assumptions in Psychology There are many philosophical assumptions underlying psychology Parsimony: given two possible explanations, the simpler is the better (Occam’s razor) Falsifiability: if a theory/explanation isn’t falsifiable, it can’t be studied (e.g., Freudian theory) Nonexistence of ‘proof’: we can support but we cannot ‘prove’ How can we know anything? If you think about it, the inside of your own mind is the only thing you can be sure of. Whatever you believe whether it's about the sun, moon, and stars … other people, even the existence of your own body - is based on your experiences and thoughts, feelings and sense impressions. Nagel (1987) Nagel (1987) echoes Descartes’ (1637) famous conclusion “Cogito ergo sum” (I think, therefore I am) Descartes used radical reasoning (doubting everything) to determine the foundation of knowledge – whilst other knowledge could be false, or a figment of the imagination, he could not doubt that he was doubting. Thus doubting his existence supported the mind’s existence! Descartes and Dualism [O]n the one hand I have a clear and distinct idea of myself, in so far as I am simply a thinking, nonextended thing [that is, a mind], and on the other hand I have a distinct idea of body, in so far as this is simply an extended, non-thinking thing. And accordingly, it is certain that I am really distinct from my body, and can exist without it Descartes Meditations VI (1641) Descartes and Dualism According to Cartesian dualism, the mind and the body are two different kinds of thing: Bodies are physical, present in space, and obey the natural laws (e.g., physics, chemistry), i.e., the physical stuff that moves, walks, and talks Minds are not physical, are not present in space, and are not subject to natural laws, i.e., the non-physical stuff that thinks, doubts and remembers Descartes and Dualism According to Descartes, the mind and body differ in their essential qualities: Minds – think Bodies – extend in space Though the mind never extends in space and the body never thinks, the mind and body affect each other: Hitting a finger (body) with a hammer results in the thought of pain in the mind Descartes and Dualism But if the mind is immaterial (non-physical), how can it affect the material (physical) body? This forms part of the ‘mind-body problem’ Descartes suggested that the pineal gland was where the mind and body interacted – he believed it was the seat of the soul and where all thought originated We now know that the pineal glad is an endocrine gland that produces melatonin! What is science? According to the Science Council (https://sciencecouncil.org/aboutscience/our-definition-of-science/): “Science is the pursuit and application of knowledge and understanding of the natural and social world following a systematic methodology based on evidence” Does psychology fit the definition? Induction vs deduction Until about a century ago science was based on a form of logical reasoning called induction Induction : the scientist collects facts and induces a general law on the basis of the facts Inductive generalisations are never ‘proved’ – they are only true to a certain level of probability e.g., All swans are white The sun always rises in the east and sets in the west Induction vs Deduction Popper (1950) challenged the inductive method and proposed an alternative scientific method: falsificationism Falsificationism is based on the logic of deduction rather than induction Falsificationism Instead of starting by collecting facts, scientists start with a hypothesis (a guess about what is true about the world) The hypothesis leads to predictions which are tested: the scientists deduces a fact that should be true if the hypothesis is true and then collects observational data to determine whether the fact occurs For Popper, a theory cannot be scientific unless it can be proved false – the job of scientists is to continually test their theories by trying to disprove them Scientific knowledge is always provisional and never ‘proven’ Induction vs Deduction The Scientific Method The Scientific Method was first described by Sir Francis Bacon (1561-1626), aiming to offer a framework for logical, rational problem solving in science The basic steps are: 1) Make an observation that describes a problem 2) Form a hypothesis 3) Test the predictions of the hypothesis 4) Draw conclusions and, if necessary, revise or refute the hypothesis Does psychology fulfil the criteria for a science? According to Popper (1950) a crucial criterion of science is that it meets the criterion of falsifiability. Therefore, an academic discipline is a science if it has hypotheses that are falsifiable A statement is scientific if it can be shown to be false through observation (e.g., It will be sunny tomorrow) A statement is metaphysical (i.e., not scientific) if it can not be shown to be false through observation (e.g., There is a small teapot orbiting the sun that is too small to be seen with telescopes) Does psychology fulfil the criteria for a science? Psychology is considered a science because its hypotheses are falsifiable – hypotheses are tested by gathering experimental data (observation); data support (nb not prove!) or refute a hypothesis Does psychology fulfil the criteria for a science? Summary Many philosophical assumptions underly psychology, including empiricism, measurability, parsimony, falsifiability and nonexistence of proof Descartes reasoned that the mind and body are distinct (Cartesian dualism): bodies are physical, present in space, and obey the natural laws; minds are not physical, are not present in space, and are not subject to natural laws Induction: the scientist collects facts and induces a general law on the basis of the facts Deduction: the scientist starts with a hypothesis and tests the predictions of the hypothesis by collecting observational data Falsification: Popper (1950) proposed that scientific disciplines use falsifiable hypotheses; a theory is not scientific if it cannot be proven false As psychology (or good psychology!) uses falsifiable hypotheses and bases knowledge on observational data, psychology meets Popper’s criterion for being a science