Critical Thinking Core Concepts

Using and Criticizing Analogies in premises:

In the first instance, an analogy can be used to argue (or convince) that something will have a characteristic based on its other characteristics. (i.e.- if an animal has a kidney, it has a heart, since all animals thus far found with kidneys also have hearts.)

In the second instance, An analogy is a comparison of one situation to another, with the purpose of clarifying certain points about the case in question by focusing on similar points in a more familiar case. In this sense, we focus on the similarities of the cases and try to ignore the (usually obvious) dissimilarities.

In either instance, a good analogy will:

1. be clear and understandable- i.e.- somewhat more common to the understanding/experience of the audience than the argument in question. It should help us to better understand a complex issue or point.
2. focus our reason on the relevant points of the claim being made- in short- the analogous situation should not be more controversial/complex than the situation it is intended to explain.
3. preserve the relationship of the premises to the conclusion- the parallels drawn must be similar in all cases.

• Let us suppose that the universe is like a clock- both have parts which move in a certain, fixed manner. Both have functions or parts which have a precise nature and function, and which follow certain fixed laws. In the case of the watch, we know that this organization is directed towards some purpose- in short- telling time. While we may not be able to tell what the purpose of the universe is, we can conclude that, like the watch, it does indeed have a purpose. In addition, since the watch has a maker, we can also conclude that the universe has a maker as well.

The use of analogies can be fruitful either in an argument or outside of one. Inside of an argument, they can distance us from the emotional aspects of a topic so that we can focus on the relevant issues and make a more reasonable decision. (example- many of the analogies used in serious abortion arguments.)

Outside of an argument, we can use an analogy to better understand a difficult topic. In some cases, they can lead us to look at a topic or idea in a new way- one which may lead to new insights which prove valuable to our understanding of the topic. These new insights will have to be proven independently - we can't use the analogy to prove it, but it can be used to better understand it. (example- looking at the activity of the mind as being like the activity of a computer)

On the flip side, as with any of the argument techniques, an analogy can be used to deceive us or to hide facts from us, or even to confuse our thinking, therefore preventing us from discovering the truth. (many comparisons with the Nazis can be seen in this light).

To this end, we can now look at two ways to criticize or attack the use of an analogy:

• Challenge the similarity-

We can- challenge the assertion that the conclusion is the result of the similarities- (example of the president being like the captain of a football team- You don't tackle the captain)

Technique #1- The goal of an administration is different from the goal of a football team- the goal of the administration is to make wise decisions, the goal of a team is to win game.

(this tactic questions the conclusion drawn from the stated goals - so- if we point to the dissimilarity of the goals- we see that the asserted conclusion (don't criticize the Pres) is less likely to be true- i.e.- effective in reaching the goal.

The tactic here is to point out a relevant dissimilarity between the two cases.

• Challenge the Premises-

For example- in the president/captain analogy, we can agree that we usually do not want to tackle the QB- but if they are running the wrong way- it may be extremely appropriate. In this case we accept the basic analogy, but disagree with the conclusion drawn from it.

Example Course Exercise: Analogies used in debates over Moral issues.

   "But now let me ask you to imagine this. You wake up in the morning and find yourself back to back in bed with an unconscious violinist. A famous unconscious violinist. He has been found to have a fatal kidney ailment, and the Society     of Music Lovers has canvassed all the available medical records and found that you alone have the right blood type to help. They have therefore kidnapped you, and last night the violinist's circulatory system was plugged into yours, so that your kidneys can be used to extract poisons from his blood as well as your own. The director of the hospital now tells you, "Look, we're sorry the Society of Music Lovers did this to you-we would never have permitted it if we had known. But still, they did it, and the violinist now is plugged
into you. To unplug you would be to kill him. But never mind, it's only for nine months. By then he will have recovered from his ailment, and can safely be unplugged from you." Is it morally incumbent on you to accede to this situation? No doubt it would be very r~ice of you if you did, a great kindness. But do you have to accede to it? What if it were not nine months, but nine years? Or longer still? What if the director of the hospital says, "Tough luck, I agree, but you've now got to stay in bed, with the violinist plugged into you, for therest of your life. Because remember this. All persons have a right to life, and violinists are persons. Granted you have a right to decide what happens in and to your body, but a person's right to life outweighs your right to decide what happens in and to your body. So you cannot ever be unplugged from him." I imagine you would regard this as outrageous,which suggests that something really is wrong with that plausible-sounding argument I mentioned a moment ago." (Judy Jarvis-Thomson, A Defense of Abortion; Philosophy and Public Affairs, Vol 1, no. 1; Princeton University Press 1971)

In this analogy, the violinist is supposed to represent the fetus, the music lovers society the rapist, and the fatal disease of the violinist represents the dependancy of the fetus on the mother .  Are all the relevant characteristics preserved?  (Have class decide) Would this same analogy work for other pregnancies that the mother wished to terminate?

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Last modified: 03/02/04