What is Science?

Question 1

What is a science?

Answer 1

Any field of study

Question 2

What is science?

Answer 2

Natural sciences e.g. bio, chem, physics

methods used by them and the knowledge derived from them

Question 3

What did Hippocrates say?

Answer 3

The theory of the 4 ‘humors’:
black bile, yellow bile, blood and phlegm

disease is caused by an imbalance in the humors
many conditions can be treated by bleeding to rebalance the humors

standard medical practise for 2000 years

Question 4

What did Aristotle say?

Answer 4

He included observation of the real world as a key to ‘natural philosophy’

Question 5

Where did modern science originate from?

Answer 5

Islamic world
Ibn Al-Haytham (Alhazen)

Then taken up in mediaval Europe
Roger Bacon

Question 6

What does science assume?

Answer 6

that the universe runs on natural laws

doesn’t have to reject religion but of necessity, rejects supernatural explanations of natural phenomena

Question 7

What are the first steps of science?

Answer 7

Observation
Exploration
Classification

Question 8

What is induction?

Answer 8

inference of a generalised conclusion from particular substances

investigating unknown
looking for repeated pattern
devising theories and laws that will explain multiple patterns

Question 9

What do scientists use to test ideas?

Answer 9

Experiments

Question 10

What is the hypo-deductive method?

Answer 10

observation –> hypothesis –> predictions –> test

test can have 2 outcomes:

1. predictions refuted (back to beginning)
2. predictions confirmed (move on)

Question 11

What is refutation?

Answer 11

Karl Popper
A scientific theory is a theory that makes predictions that are capable of refutation

If theory is wrong then predictions will be wrong
if predictions are correct then theory is potentially right

Question 12

Where is the scientific approach useful?

Answer 12

useful in the world in general

e. g. clinical practise
- clinician examines patient and makes a hypothesis about possible diagnosis
- but if too attached to own hypothesis then fail to consider it might be wrong

Question 13

In real life, single experiment can’t conclusively prove or disprove anything. Why?

Answer 13

1. Experiments depend on assumptions
2. At cutting edge of science, do not fully understand what we are doing
3. May be other experiments giving contradictory results

Question 14

What contributes to scientific confidence?

Answer 14

Requires multiple independent lines of evidence

plus believable theory to make sense of the evidence

Question 15

Explain the history of cholera

Answer 15

in early 19th century, dominant theory f epidemics was that they were caused by ‘miasma’, carried in air and detectedby bad smell

John Snow

• studied cholera epidemics in London and suggested that the outbreak in Soho was limites to families drinking water from particular pump
• removed handle from pump, epidemice ended shortly afterwards

Question 16

What are paradigms?

Answer 16

‘A body of agreed knowledge and ways of working’ - Thomas Kuhn

Now have

Question 17

Why are paradigms important?

Answer 17

John Snow - evidence that cholera spread in drinking water
Wendell Holmes and Ignaz
Semmelweis- evidence that childbirth fever spread by obstetricians
but not widely believed by doctors

Louis Pasteur - experimental demonstration of germs
Pasteur and Koch: demonstration that bacteria cause disease
- isolation and culture of disease organisms
- culture methods, agar plates, staining methods

Question 18

What is relativism?

Answer 18

The concept that different ways of looking at things are equally valid (as long as they are internally consistent)

Question 19

What is homeopathy?

Answer 19

Theory - take a toxin that causes the same symptoms as the disease
-dilute it enormously and it will now cure the disease

But toxin is usually diluted to less than 1 molecule per tube
If homeopathy is correct then atomic theory of matter is wrong