Science CommunicationLOLO.00.037

www.ut.ee/BG/scom

Session 2The Nature of Science

Jack Holbrook

University of Tartu

The Overall Goal

Developing an understanding of :

• What science is and what it is not.

• What science can do and what it cannot do.

• How science contributes to culture.

Some Assumptions about Scientific Knowledge

THE WORLD IS REAL

In other words, the physical universe really does exists, apart from our sensory perception of it.

Another Assumption

HUMANS CAN PERCEIVE AND UNDERSTAND THE PHYSICAL UNIVERSE.

In other words, we can learn about how the natural world (as opposed to the supernatural world) works and operates.

A Third Assumption

NATURAL PROCESSES are SUFFICIENT to explain, or account for natural phenomena or events.

In other words, scientists must explain the natural in terms of the natural.

Last Assumption

Scientists ASSUME THAT NATURE "OPERATES" UNIFORMLY

in both space and time

(unless we have evidence to the contrary).

This is known as the

PRINCIPLE OF UNIFORMITY.

The Scientific Process

Would you support the idea that ‘scientific’ means involvement of -

Observations followed by Inferences ?

Observations are important as they lead us on the path to being a successful scientist, or to gain an understanding of the real world.

Observations followed by Inferences

Comment on observations made in the natural world.

• Would you be willing to accept that scientific observations are unambiguous and give the ‘real’ picture?

• If so, take a look at the following -

Does A or B form the straight line extension of line C ?

Could we make a mistake in our observations without realising it ?

Are the lines at the top of the trapezia of different lengths ?

Could we inadvertently give false information ?

How many f’s ?Answer within 5 seconds

Finished files are the resultof years of scientific studycombined with the experienceof years...

Are we good at making complete observations ?

Observing scientifically

You may have difficulty in observing correctly, but scientists have no problem.

Or do they ??

Let us observe more.

A rabbit or a duck?

An Illusion

• Do you see a face?

• Or an Eskimo?

Can you see the three faces?

                                                      

Can you see 3 faces ?

How many faces or people do you see ?

Can you find the 13 hidden faces?

                                                                                                                                                               

Buy a poster!

How many hidden faces?

The picture shows a waterfall to the side of the house.

But are you sure ??

I have another clip similar to the previous one

Take a look

Is this physically possible?

Going up or down ? Maybe neither !

Just a slice of bread !

Can you see a man ?

What do you see – man or woman?

May I invite everyone to leave their seat and observe from closer to the screen. Then move to the back of the room.

Additional sources of illusions

• www.eyetricks.com

Observations

• Scientific observation needs to be objective.

• But is this always possible ? • It would seem there is a human element that

interferes with absolute objectivity.

• Could it be that scientific observations are subjective ?

Observation and Inference

Science is based on both observation and inference.

Observations are gathered through human senses or extensions of those senses.

Inferences are interpretations of those observations.

But is there more to being ‘scientific’?

For example, what about being inquisitive?

(Inquisitiveness may be shown by asking questions)

Try the following ACTIVITIES

Examining a cube

Create a group of 3/4 persons. Sit around a table facing each other in the group.Examine (but do not touch/move) a cube which is

placed on top of a plastic cup on the table.

Being inquisitive !

• Can you (individually) put forward a question to ask about the cube ?

• Please record the diversity of questions coming from the persons in the group.

What is written on the bottom, i.e. on the hidden side of the cube?

• In your group, discuss this question.

• Record your group prediction(s).

• If you feel it is useful, your group may give more than one justification.

Now – try to justify your predictions.

And, if you have more than one prediction, identify the one your group considers to be dominant.

Examining another cube

The previous exercise was (I hope) simple. (school students find it easy)

• NOW, in your groups, examine (but do not touch/move) a new cube placed on the plastic cup.

• AGAIN put forward your predicted response to what is on the hidden, bottom face of the cube.

• AGAIN record your prediction(s).

Cube 3 - A further stage

• Carefully raise one corner of the cube so that, with the use of a mirror, you can see the number recorded in the top right corner, OR the bottom left corner (but not both !!)

• Modify (add to) your prediction as to what is written on the bottom of the cube.

• TRY TO GIVE A FULL PREDICTION COVERING ALL THAT IS WRITTEN.

Cube 3 and degree of observation

Does cube 3 give us any insight into the scientific approach ?

Does it suggest that we do not necessarily need to observe everything and that we can make calculated guesses from other observations ?

Make inferences on incomplete observations . • If a gas is colourless and lighter than air, can we infer it

is probably hydrogen ?• Or if a gas is known to be hydrogen, then can we infer a

balloon containing hydrogen will …..

Aoccdrnig to rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoatnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit a porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.

The Importance of Inference

Try reading the passage below

Acting the scientific way

If inference skill is a key to being ‘scientific’,

even if observation is incomplete,

what about making predictions ?

Observe what does actually happen.

What explanation do you have for what happened? You should be able to put forward at least one explanation. Explanations from the group may not all be the same.

Select one explanation which you like. Now based on that possible explanation, predict what will happen when the second hole is uncovered.

Observe what actually did happen.

Did the result match your prediction ?

If so, do you feel your prediction is good?

If NOT, it seems your prediction is not good.

Can you put forward another Prediction?

Now we have one more hole. Let us again make a prediction about the outcome if we uncover all 3 holes.

Summarising

• Science is limited to operations within certain boundaries (assumptions).

• Observations are scientific, but not always easy.• Inferences are scientific and often can be made

with incomplete observation.• Making predictions is an important scientific

attribute, as are putting forward explanations.

• So why is school (university) science so much about knowing facts ?

Session 3

Individual presentation

Taking whatever optical illusion you wish, please present this to the group (from powerpoint or from the internet, or as a live demonstration).

The challenge

In doing this, please pay attention to the need to present to the audience (not the screen or the ceiling/floor) and please note the audience needs to understand the point of your presentation.