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THE METHODS OF SCIENCE AND THOUGHT EXPERIMENT IN EMPIRICAL SCIENCE

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Students understand science as methodical because they know the meticulous setup of an experiment.
But does science monopolize experiment?
And, is experiment science’s only method?

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In fact, the concept of an experiment comes naturally to us.
A child learns from his mistakes: if he remembers that last time he touched an object and he got pinprick feelings in his fingers, he will probably avoid touching it this time.
Or, he may try again and gets the unpleasant feeling again.
So, now he has in mind the hypothesis: that surface always “bites” my fingers without me seeing it.
Well, the child has set up a simple experiment to test his hunches.

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THOUGHT EXPERIMENT

So, it may be said that experiment need not be something technical and sophisticated.
Furthermore, equipment is not a must.
Of course, the simplest kind of experiment is by thinking alone: thought experiment.
The ancient people 3000 years ago already showed incredible ability to observe the night sky and recorded the positions of stars at different times. That’s why they could predict the return of a comet and invent the calendar.

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EMPIRICAL

Without complicating the picture, let’s agree that in the most basic sense, a scientific experiment consists in designing a way to collect and interpret data from the world with the purpose to verify or refute some hypotheses about the world.
The data-dependence is the reason why we call science an empirical discipline.
Of course, we should recall that the scope of science is what we normally call the physical world. Hence, so long as we don’t regard interpersonal relationship or the stock market literally part of the physical world, the study of sociology or business cannot be labeled science even though people still use a lot of experimental methods there.

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No doubt, the ancient people regarded the movement of the celestial bodies as the object of scientific studies because for them, motion and rest are clearly two important parameters that apply to every physical thing in the world.
This idea is in fact not far from the truth even by today’s standard.
In a way, we see how measurement is intimately tied to science: movement in terms of distance and time is quantifiable.

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Let us see several famous scientific experiments: either real or merely being thought about.

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NEWTON’S ROTATING BUCKET

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ARCHIMEDES’S BATHTUB

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GALILEO'S FREE FALL

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EINSTEIN’S TRAIN

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DOUBLE-SLIT EXPERIMENT

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ARCHIMEDES’S LEVER

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KEKULE’S DREAM OF THE SNAKE

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SOLAR ECLIPSE

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METHOD

Step 1: Always have a hypothesis in mind. The aim of the experiment that follows is to confirm or refute the hypothesis.
Step 2: Define the data that are to be collected and specify how this is done and the data to be measured.
Step 3: Decide if the results confirm or refute the hypothesis.

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CRUCIAL EXPERIMENT

Recall Bacon’s emphasis on experiment.
He had the further concept of a kind of experiment that will definitively settle the problem at hand.
This is called the crucial experiment.

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EXERCISE

Design an experiment to confirm whether a person getting facial paralysis within two days after vaccination is a real side effect.

Design an experiment to disconfirm that there are ghosts.

Design an experiment to confirm that rich people are happier than poor people.

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We have previously learnt the language of science.
Now it is time we combined such knowledge with the actual understanding and implementation of a scientific experiment.

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HD METHOD

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ENUMERATIVE INDUCTION

In the process of inductive inference, we obtain data from a finite number of observations and attempt to generalize from them.
This process is sometimes called enumerative induction.
For example, if the swans you have seen so far are all white, you might be tempted to generalize that swans must be white.

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There is a tight and intricate connection between the use of deductive and inductive reasoning.

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PREDICTION

The future has not happened. But we believe that with laws and past events, we might be able to make good prediction.
For example, weather forecast is nowadays quite reliable.
What about gambling? Can you predict the outcome of Mark Six based on past records? What about predicting the winning team of a soccer game?

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Even ordinary people try to be scientific when they gather data and do fact-checking: the data and facts help them to predict accurately.
You may even say that your decision to apply by non-JUPAS to HKU later a product of scientific reasoning because you have analyzed (how?) data about past cases, etc.

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The surprising thing about human is that we on the one hand believe that it is easy to predict about the behavior of our acquaintances and yet we are so often bitterly surprised by them.
Hence, think carefully whether you consider psychology a scientific subject.
Similarly, economics is about mass psychology and prediction.
What kind of laws are operating in these subjects?

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FALSIFICATION

An unorthodox view of science is that what the scientists do is not to prove something. Instead, they perform experiments only trying to show some theories to be false.
Karl Popper’s view is called falsificationism.
Of course, so long as a theory has not been falsified, we should be happy to continue believing and using it.
But note that there is a type of theory that we can never falsify no matter what. Popper calls those theories pseudo-science.

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PSEUDO-SCIENCE

The reason why those theories are so resilient is not that they are robust. Instead, it is in the nature of such theories that there are always “reasonable” exceptions.
Popper’s example is Freudian psychoanalysis and Marxism.
You may also come up with your own list such as astrology and palm reading, etc.
The problem for us is to demarcate between real science and pseudo-science.

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HAVE YOU THOUGHT ABOUT YOUR PRESENTATION TOPIC?

Things to consider:
1. Do I have an issue related to science that I want to talk about?
2. Do I have a project in a science course that can be extended to the presentation in this course?
3. Is there any topic in the course that you have some confidence and interest in?
4. Are the several ready-made topics with assigned readings (such as memes, cyborg, religion and technology) agreeable?