I recommend taking the chapter 1 and 2 quiz before and after reading the first two chapters (to access the quizzes, click the 'fun quizzes' link at the top of this page).

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Argument Video

Introduction: This chapter is mostly a vocabulary lesson in that it attaches technical terms to the rational thinking you already do on a daily basis.

Concept: We philosophers use the word “argument” in a different way than you may use it in everyday life. In Philosophy, an argument is not a disagreement or yelling match. An argument is a claim (called a conclusion) supported by other claims (called premises). It may be easier to think of the conclusion as what you are trying to prove and the premises as the evidence. Consider the following argument:

Premise 1: The universe is either goes back infinitely or it has a beginning.

Premise 2: The universe cannot go back infinitely (because energy cannot cross an infinite time to get here).

Conclusion: The universe has a beginning.

Notice that arguments are like math problems. When you add up the premises, they supposedly equal (or support) the sum that is the conclusion. Notice too that every argument has exactly one conclusion, but may have any number of premises. Complete the following exercises to reinforce this concept.

Exercise 1: Underline the conclusion and circle the premise(s) in the following arguments. Check your answers below.  

1.  The universe must go back infinitely since there would have to be an uncaused first cause if it had a beginning, and an uncaused first cause is impossible.

2. If there were an infinite timeless God, finite minds could not grasp this God. Therefore, the failure to grasp God is evidence for God.

3. God probably does not exist because there is so much gratuitous suffering in the world.

4. Water is gentle, but it can erode the hardest of rocks. Therefore, you will effortlessly achieve when you act gently (derived from Taoism).

5. All men are mammals. Todd is a man. So, Todd is a mammal.

6. Your value lies in what is not within (i.e. ego). After all, the value of cups, doorways, and windows is what is not there (Tao Te Ching).  

Exercise 1 Answers

  1. “The universe must be infinite” is the conclusion. It is followed by two premises. By the way, this argument might lead one to study the cosmological arguments for the existence of God. The arguments are much deeper than those presented here. 
  2. “The failure to grasp God is evidence for God” is the conclusion. It’s preceded by one premise. This argument is derived from mysticism and Simone Weil's "Hidden God."
  3. “God probably does not exist” is the conclusion. It is followed by one premise. There is also a hidden premise (i.e. enthymeme), “God would not allow gratuitous suffering.” This is a simple version of the argument evil, the most powerful argument against God's existence. 
  4. The first sentence is the premise and the second is the conclusion.
  5. “Todd is a mammal” is the conclusion. It is preceded by two premises. This type of argument is called a syllogism. Syllogisms have three terms, two premises, and one conclusion.
  6. The first sentence is the conclusion. The second is the premise. We could also interpret this as an illustration instead of an argument.  

Exercise 2: Underline the conclusion, identify the premise(s), and discuss the following arguments.

  1. Killing is not always wrong because it is morally permissible to kill in self-defense.
  2. If God’s knowledge is perfect and God knows exactly what you will do in five minutes, then you must do what God knows you will do. But if you must do what God knows you will do, then you cannot act other than you will act or have acted. Therefore, you are not free.
  3. The Tao is beyond time and space. Therefore, nothing in time and space can prove or disprove the Tao.
  4. Vampires suck blood. Beings that suck blood are called phlebotomists. Therefore, vampires are phlebotomists.

Exercise 2 Answers

  1. “Killing is not always wrong” is the conclusion. One premise follows. If you believe it is always wrong to kill, you are an absolutist about killing. 
  2. “You are not free” is the conclusion. It is preceded by two premises. Free will is a major topic in philosophy/metaphysics. Most people believe in free will and are called libertarians. Hard determinists deny free will. Compatibilists redefine free will and believe it is compatible with determinism. The issue of free will brings up many complex and interesting topics. 
  3. The first sentence is the premise and the second is the conclusion.
  4. The first two sentences are premises and the third is the conclusion.

Exercise 3: Underline the conclusion, identify the premise(s), and discuss the following arguments. Notice that each of these arguments is obviously bad. Since they contain bad inferences, logicians call them “fallacies.”

  1. I’ve met three red heads and they were all mean. Ergo, all redheads are mean.
  2. You cannot prove science will not explain everything, therefore it will.
  3. I can trust my senses because your senses agree with my senses.
  4. If you give me a beer then I will be happy. I am happy. Therefore, you gave me a beer.
  5. It is natural to want to kill and eat animals. Since goodness comes from naturalness, it is good to kill and eat animals.
  6. Galileo said mathematics is the language of reality, which is why I should focus solely on the study of mathematics.

Exercise 3 Answers 

  1. The first sentence is the premise and the second is the conclusion. Notice “ergo” is a conclusion indicator. You may have noticed this is a poor argument, a hasty generalization fallacy (see chapter three on fallacies).
  2. The first sentence is the premise and the second is the conclusion. “Therefore” is a conclusion indicator. This is a poor argument, the fallacy of arguing from ignorance (see chapter three on fallacies).
  3. “I can trust my senses” is the conclusion and is followed by one premise.   “Because” is a premise indicator. This seems to be a weak argument, the fallacy of popularity or begging the question. However, it is one of the better arguments we have for trusting our senses.
  4. The last sentence begins with “therefore” and is, therefore, the conclusion. The first two sentences are the two premises. This is a poor argument, the fallacy of affirming the consequent.
  5. “It’s good to kill and eat animals” is the conclusion. The preceding two statements are the two premises. This is a weak argument, the appeal to nature fallacy.
  6. “I should focus solely on the study of mathematics” is the conclusion. This could be an appeal to authority fallacy. Some arguments could be more than one fallacy, it depends on how you interpret the structure of the argument.

To explore this section in more depth, see chapter three on fallacies.

Application and Value

As you do philosophy, clearly identify the premise(s) and conclusion for each argument. This takes time and effort, but you should accurately identify arguments before evaluating them. It improves the quality of discussion and helps you avoid straw men.

For more practice, download my logic workbook or take my fun quizzes

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