POH|(ENG)Chapter 1.1-1.2 Introduction to logic, study of argumentation, and background theories.

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POH, Philosophy of Humanities, a series of online courses of Leiden University aiming at discussing the philosophy behind humanity subjects including history, sociology, global politics and etc. However, its first and second chapter introduces the philosophy of sciences as well. I would highly recommend this course to students studying all humanity subjects as well as anyone interested in Philosophy. No previous knowledge of philosophy is required. However, the course is currently only available in English. The link to the course is here:

https://www.youtube.com/watch?v=K4ChzesrWKI&list=PLPeStI124dee1ByfcDzRvPxKDNb0GQjmo?

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chapter 1.1-1.2 are actually informative. They build up some basic ideas of philosophy for new starters. However, Im putting their notes together because they really are, as I mentioned, very basic ideas. I assume that the majority of my readers dont necessarily need to study for this part of the series.

Chapter 1.1 INTRODUCTION TO LOGIC

List of key concepts

• Premises and conclusion
• Valid and invalid arguments
• Inductive and deductive arguments
• Aristotle and interesting facts about deductive arguments

Why do we study logic?

Because its the study of argumentation.

What are the basic components of an argument?

Therere two main parts that an argument is consists of---premises and conclusion. Premises is what we presuppose.(Kind of like evidences) Conclusion is what we conclude from the premises.

Validity of arguments

Therere two types of argument, valid argument and invalid argument. A valid argument is where the conclusion really follows the premises. Invalid argument, on the other hand, is an argument thats not valid. This could be because the premises are irrelevant to the conclusion and etc.

Lets look at an example from the course of an invalid argument:

This example is absolutely invalid because it doesnt make any sense to draw the conclusion from our premises. However, if we change the second premise into:

Louis VII of France was a great medieval king.

Then it would be a great example of a valid argument.

Whether an argument is valid or not has nothing to do with whether or not the premises and conclusions are true or not. (We only look at if the conclusion follows the premises of an argument to determine whether or not its valid. Its possible that we have an argument where all premises are false yet the argument is still valid. We just end up having a false argument but still, it could be valid. )

Deductive and inductive argument

A deductive argument is an valid argument in which the truth of the premises absolutely guarantees the truth of the conclusion. However, an inductive argument (also valid) is where the truth of the premises gives good reasons to believe the conclusion, but doesnt absolutely guarantee the truth of the conclusion.

Heres an example of an inductive argument:

Facts about deductive arguments

If you use deductive arguments, you cannot make any new mistakes. The only way that a conclusion in a deductive argument is false, is that its assumptions is false. (Thus, using them is not risky. And you would know your conclusions to be false before you reach them. )

Aristotle and form of an argument

Whether a deductive argument is valid or not can be determined just by looking at the form of the argument and ignoring its content. (Aristotle found out this)

For example,

No A is B,

C is A.

So no C is B.

Thus, we realize that we can see whether something is a good (deductive argument) without making any prior theoretical assumptions about the content matter.

Which means in science, if scientists only use deductive arguments, the process of conclude a theory should be:

Data-------->conclusion(Theory)

It would be great if our sciences work like this. However, partially because of our limited data, most scientific arguments are inductive arguments.

Chapter 1.2 INTRODUCTION TO BACKGROUND LOGIC

List of key concepts

• logic form

Focus

In order to see if an inductive argument is any good you always need to use background theories. Which means you have to use induction. We cannot derive theories from neutral data, we are always relying on some theoretical beliefs. (Presuppositions, or even prejudges)

What about scientific research?

As we mentioned in Chapter 1.1, most scientific arguments are inductive arguments. This is partially because drawing conclusions from data is always going to require induction. Why?

The answer is that we always need background theories about the content in order to assess whether a supposed inductive argument is any good.

Two example arguments from the same logic form.

The logic form is:

I did A 25 times and every time B happened,

So every time I will do A, B will happen.

This is definitely a logic form of an inductive argument, thus, we cannot tell whether or not its a valid argument just by looking at its logic form.

Lets put different contents into A and B and see how the results could be very different even if were using the same logic form.

A: put my hands in hot stove. B: it hurts.

1. A: ask a question in Dutch. B: receive an answer in Dutch.

The first argument would look like:

I put my hands on a hot stove for 25 times and every time it hurts.

So every time I put my hands on a hot stove, it will hurt.

Our background knowledge on human body (That putting our hands on hot stuff does hurts) would absolutely make us believe this argument.

However, the second argument would look like:

I asked a question in Dutch and received all answers in Dutch.

So every time I ask an answer in Dutch, I will receive an answer in Dutch.

This time, our background knowledge on the diversity of human language would quite contrarily made us doubt this.

We can see from these two examples that we did assessed the arguments depending on the relative background theories that we already had in mind, rather than on simply the data themselves.

Two things that we need to know in order to assess an inductive argument

1. How possible is it that the things were interested in behave uniformly (Less possibility means that more evidences are needed)
2. Whether the data that we have are representative.

Conclusion

Inductive arguments in which we draw general conclusions from our observations (data) can only be judged based on certain background theories.

Thus, all scientists are a bit of "Biased" because they all draw conclusions based on their background theoretical knowledge. No scientists are focused on the data only.

Interestingly, this explains why scientific theories arent digestible for everyone. Because not everyone can have the background knowledge as much as the scientists who drawn the theories do.

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