Introducing the Philosophy of Science Lecturer: Vincent Zungu - - PowerPoint PPT Presentation

introducing the philosophy of science
SMART_READER_LITE
LIVE PREVIEW

Introducing the Philosophy of Science Lecturer: Vincent Zungu - - PowerPoint PPT Presentation

Introducing the Philosophy of Science Lecturer: Vincent Zungu Source: Chalmers, A.F. 2005. What is this thing called Science. Open University Press. Maidenhead . Unprejudiced seeing? Two people viewing the same object do not always see


slide-1
SLIDE 1

Introducing the Philosophy of Science

Lecturer: Vincent Zungu Source: Chalmers, A.F. 2005. What is this thing called Science. Open University

  • Press. Maidenhead.
slide-2
SLIDE 2

“Unprejudiced seeing?”

  • Two people viewing the same object do not

always see the same thing. Figure 1 on page 6.

  • What do you see? Is it a staircase or just a

collection of lines. If it is a staircase, is it

  • ne from above or below?
slide-3
SLIDE 3

Observation: passive and private

  • r public and active
  • How observation is commonly understood

by philosophers?

  • What is observation as passive and private
  • r public and active affair?
  • What is the role of observation in Science?
slide-4
SLIDE 4

Observation: passive and private

  • r public and active
  • Common understanding of observation by

range of philosophers: seen as passive, private affair.

  • Passive – when seeing we simple open and

direct our eyes, let the information flow in, and then record what is there to be seen.

  • Private – it is the perception itself in the

mind that is taken to directly validate the

  • bservable facts.
slide-5
SLIDE 5

Observation: passive and private

  • r public and active
  • Example – One can see that an object in

front of his is a Tomato!

  • Note- the above act is accomplished by

individual closely attending to what is presented to him/her in the act of percetion

  • However- it does not provide an accurate

account of perception in everyday life or even in science.

  • There are range of things that are done to

establish the validity of perception.

slide-6
SLIDE 6

Observation in Science Public and Active

  • Our task is to consider the role of
  • bservation in science.
  • E.g. the early use of microscope in science.
  • Robert Hooke and Henry Powers used the

microscope to look at the small insects and ants.

  • These scientists often disagree about
  • bservable facts initially. Hooke traced the

nature of the disagreements.

slide-7
SLIDE 7

Observation in Science Public and Active

  • He pointed out that the eye of a fly appears

like a lattice covered with holes in one kind

  • f a light.
  • Powers agreed but also mentioned that it

appears like a surface covered with cones in another and in yet another light like a surface covered with pyramids.

– Important to note that above scholars sees the same objects but with different descriptions. – The question: is which one of these provides accurate description?

slide-8
SLIDE 8

Observation in Science Public and Active

  • Hooke then proceeded to make practical

intervention designed to clear up the

  • problem. How?
  • Eliminate spurious information arising from

dazzle and complicated reflections by illuminating specimens uniformly.

  • Micrographia (1665) book came out with

many detailed descriptions and drawings that resulted from Hooke’s actions and

  • bservations.
slide-9
SLIDE 9

Observation in Science Public and Active

  • These productions were and are public, not

private.

  • They can be checked, criticised and added to

by others.

  • Therefore the observable facts about the

structure of a fly’s eye that eventuate result from a process that is both active and public.

  • If actions are taken to explore the validity of

claims – thus subjective aspects of perception need not to be a problem for science

slide-10
SLIDE 10

Observation in Science

  • Perceptions of the same scene can vary

from observer to observer – their background, culture and expectations.

  • This problem can be eliminated by taking

appropriate action.

  • The perceptual judgements of individuals

can be unreliable for a range of reasons.

  • Challenge: in science is to arrange the
  • bservable situation in way that the reliance
  • n such judgments is minimised.
slide-11
SLIDE 11

Observation in Science

Vertical View Horizontal View

slide-12
SLIDE 12

Observation in Science

  • Moon illusion is a common phenomenon.
  • High in the sky – appears much smaller

than when it is low on the horizon.

  • However – do not have to put trust on the

subjective judgement about the moon size

  • But what do we do to reduce subjective

view of the moon size.

  • Can mount a sighting tube fitted with cross

wires – so that its orientation can be read on a scale.

slide-13
SLIDE 13

Observation in Science

  • This can be done when the Moon is high on

the sky and repeatedly done when it is horizontal.

  • Findings- the moon remain unchanged –

indicating that there is no significant variations and differences between the scale readings in two cases.

slide-14
SLIDE 14

Observation in Science

  • Key points to learn:
  • Observation statement constitute worthy of

forming basis for science – straightforwardly tested by senses and withstands those tests.

  • OS – their validity can be tested in ways

that involve routine, objective procedures that do not necessitate fine, subjective judgements on the part of observer.

  • This brings out the Active, public character
  • f the vindication of OS.
slide-15
SLIDE 15

Observation in Science

  • Small price has to be paid for the notion of

an observable fact (OF).

  • That price is that (OF) are to some degree

fallible and subject to revision.

  • If OF passed the testes – does not mean that

it will survive new kinds of tests that become possible in the light of advances in knowledge and technology.

  • E.G. The earth is Stationary and second –

the apparent size of Mars and Venus do not change appreciably during the course of the year.

slide-16
SLIDE 16

Observation in Science

  • Therefore we can conclude that observation

worthy of forming basis for scientific knowledge are both objective and fallible.

  • Objective – because they can be publicly

tested by straightforward procedures And

  • Fallible – they may be undermined by new

kinds of tests made possible by advances in science and technology

slide-17
SLIDE 17

Essay Question ?

  • Discuss how observation statement can

form the basis for scientific knowledge. Answer your question by providing relevant examples to show understanding of the

  • topic. (Essay must be 5 pages!!!). Due date:

15 August 2011)