2. Attack and support relations

2. Attack and support relations
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2.1. How does an argument attack or support a sentence?

An argument supports a sentence if the conclusion of the argument is equivalent to the sentence, or if they are identical. An argument attacks a sentence if the conclusion of the argument is contradictory to the sentence. (Thus, they cannot both be true at the same time.)

2.2. How does an argument attack or support another argument?

In a similar manner, an argument can also attack or support another argument. An argument supports another argument if the conclusion of the supporting argument is equivalent to one of the supported argument's premisses. An argument attacks another argument if the conclusion of the attacking argument is contradictory to one of the attacked argument's premisses.

Note

Assumptions, preliminary conclusions or conclusions of an argument cannot be attacked or supported.

In contrast to the sketching of arguments, where the relations between arguments are represented by dashed arrows ( Chapter 2, Sketching a debate ), the relations between reconstructed arguments are represented by solid lines.

The argument you have just reconstructed has the conclusion "Software should be patentable", which is the central thesis of the debate about software patents. So the "Intellectual property" argument supports the central thesis. This relation was already sketched in the previous tutorial. Before stating this relation more precisely using the reconstruction wizard, the sketched relation has to be deleted.

2.3. Deleting a sketched relation

Select the sketched support relation between the argument "Intellectual Property" and the central thesis by clicking on the green dashed arrow on the argument map.
Press the Remove button or press the DELETE-KEY .

2.4. Supporting a sentence

You will now reconstruct the support relation between the argument and the sentence.

Pressing the left mouse button, drag an arrow from the "Intellectual Property" argument to the central thesis. When the mouse button is released, four buttons appear.
Click the Support Arrow button .

A green solid arrow appears. Unlike the dashed arrow representing sketched support, the solid arrow represents the logical relation between the conclusion of the argument and the supported sentence.

Figure 3.6. A reconstructed support

2.5. Attacking an argument

The "Intellectual Property" argument can also be attacked or supported. You will now reconstruct an attack on the second premiss ("Software is intellectual property") and also a support relation for this premiss. We will begin with the attack. Please create an argument on your argument map that corresponds to the following illustration.

Figure 3.7. Reconstruction of the argument "Mathematical Algorithms"

The argument's conclusion is contradictory to the first premiss of the "Intellectual Property" argument and therefore attacks this argument. The next step is to reconstruct this attack using the reconstruction wizard.

Pressing the left mouse button, drag an arrow from the "Mathematical Algorithms" argument to the "Intellectual Property" argument. When the mouse button is released, four buttons appear.
Click the Attack Arrow button . The reconstruction wizard "Attack" opens.

Figure 3.8. The reconstruction wizard "attack"
The reconstruction wizard offers several options for the reconstruction of relations between arguments. Either the negation of the attacking argument's conclusion is added to the attacked argument as a premiss, or you define the semantic relation between the conclusion of the attacking argument and an existing premiss of the attacked argument. As the "Intellectual Property" argument already contains a premiss that is contradictory to the conclusion of the argument "Mathematical Algorithms", select the second option Define New Contradiction .
You are then asked to specify the attacked argument's premiss that is contradictory to the conclusion of the attacking argument. Select the premiss "Software is intellectual property". Click the Finish button.

Figure 3.9. Selection of the attacked premiss in the reconstruction wizard "attack"

A solid red arrow appears between the two arguments on the argument map, which represents the reconstructed attack..

Figure 3.10. Argument map with reconstructed attack

2.6. Supporting an argument

We will now reconstruct an argument that supports the very same premiss that has just been attacked. Instead of beginning with the reconstruction of the argument and then defining the support relation, we will now proceed the other way round and begin by defining the supporting relation. (However, a supporting relation can also be added in exactly the same way as described above.)

Add the new argument to the argument map (left mouse click > select Insert New Argument ).
Pressing the mouse button , drag an arrow to the "Intellectual Property" argument, and release the mouse button.
Select Support Arrow from the context menu . The reconstruction wizard "Support" opens.
As the supporting argument has not been reconstructed yet, the reconstruction wizard asks you to select one of the premisses of the supported argument, which will be inserted as the conclusion into the supporting argument.
Select the premiss to be supported by the new argument, in this case "Software is intellectual property", and click Next .

Figure 3.11. Selection of the supported premiss in the reconstruction wizard "support"

Argunet automatically inserts the sentence of the premiss as the conclusion of the new argument.

The reconstruction of the argument can now be completed by adding premisses, inference patterns, etc.

Figure 3.12. The resulting argument map