Ads and syllogisms

How do we know what we know? Logic is one way. Advertisements try to appeal to our sense of logic, so that we buy into a brand or purchase a product. When studying ads we often ask ourselves" 'what are the advertisers really saying?' In order to read between the lines, we often use reasoning. Take for example this Volvo ad which reads, "Cages save lives." While there is no image of a car, we somehow know that the advertisers are trying to sell us one. We fill in the blanks: 'If cages save lives, and Volvos are built like cages, then Volvos must save lives." How do we come to this conclusion?

In this lesson we will look at the reasoning behind ads. This reasoning, as we will discover, can be quite flawed and very implicit. 

Inductive and deductive reasoning

There are two ways in which we come to conclusions: through inductive and deductive reasoning.

Inductive reasoning is where we start from specific statements and come to general rules. For example, this reasoning behind this ad for Trojan condoms could read:

Premise 1 - Girl 1, 2, 3 and 4 do not like pigs. (specific)
Premise 2 - Girl 5 likes a man.  (specific)
Conclusion - Women like men over pigs. (general)

Deductive reasoning is where we start from general rules and apply them to specific instances. For example:

Premise 1 - Women do not like pigs. (general)
Premise 2 - Pigs do not wear condoms. (general)
Conclusion - If I want to be liked by women, then I must wear a condom (specific)

Notice there is not a single condom in the entire ad. The text, however, helps us come to these conclusions. We apply another general rule that men are more advanced or 'evolved' than pigs. And we are told that using a condom every time is part of being that more evolved human being (or 'man').

Furthermore, notice that our inductive reasoning uses 'I' in the conclusion, as we often try to identify with the people in the ads. The target audience consists of men who want to be like the man who walks away with the woman. The text 'be a man' implies 'do not be a pig.'

Syllogisms and enthymemes

In the previous ads we have come to conclusions based on several statements or 'premises'. In logic, arguments are constructed though more than one proposition, or 'premises', and a conclusion. Collectively, we refer to these premises and their conclusion as 'syllogisms'. In fact you have already read two syllogisms on the Trojan ad. If we are to write one for the following ad it would read something like:

Premise 1 - Parents must be fast to help their children. (general)
Premise 2 - Adidas shoes make you fast. (general)
Conclusion - The parent of this child should buy Adidas shoes. (specific)

The problem with this syllogism is that we are filling in a lot of gaps. In fact there are only three words in this ad: 'Be fast. Adidas.' We have assumed the rest. 'Enthymemes' are incomplete syllogisms where premises must be assumed. 'Be fast. Adidas' is really an enthymeme, just as 'Cages save lives' and 'Evolve. Be a man. Use a condom every time.' Most ads are in fact enthymemes. 


Below you see several ads. These ads all imply much more than they state. For each ad try to write out a syllogism, explaining its implicit use of inductive or deductive reasoning.

"Best to keep some windows closed"

Deductive reasoning:

Premise 1 - Children should be protected from pornography and alcohol. (general)
Premise 2 - Pornography and alcohol are online. (general)
Conclusion - This child's internet browser should have a filter to keep out pornography and alcohol. (specific)

EPhone 900
"Fast Internet access when and where you need it"

Deductive reasoning:

Premise 1 - Danger can strike quickly. (general)
Premise 2 - Information is quickly accessible online. (general)
Conclusion - This person's phone can look up information faster than he can get bitten by a snake. (specific)

Inductive reasoning:

Premise 1 - The person is in the jungle. (specific)
Premise 2 - The person has Internet access in the jungle. (specific)
Conclusion - His or her phone company must provide internet access in the jungle. (general)

All human beings are born free and equal in dignity and rights


Premise 1 - All human beings are equal. (general)
Premise 2 - Humang beings have different shades of skin. (general)
Conclusion - All of the people in this image, despite their different skin colors, are equal. (specific)

Towards assessment

Written task 2 - As you deduce the messages of advertisements by using logic you may find yourself answering some of the prescribed questions for written task 2, the critical response. For example, the Benetton ads on race from the 1990s seem to break both taboos and the conventions of advertising. Read the sample written task 2 based on these Benetton ads which answer the following prescribed question:

"How does the text conform to, or deviate from, the conventions of a particular genre, and for what purpose?"

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