Argument mapping is just what you think — diagramming or documenting an argument in visual form. There’s a number of different kinds that can be identified.

A serial argument is a string of reasons and conclusions in which every conclusion is supported by one reason. Consider the following argument:

(1) Boola cars are unreliable and therefore (2) are going to cost you more in upkeep than they’re worth. So, (3) you shouldn’t buy a Boola car.

In this argument, (1) is offered as a reason for (2) — and (2) is offered as a reason for (3). Both the final conclusion (3) and the intermediate conclusion (2) are supported by one reason. It is therefore a serial argument. We diagram this argument as follows:

We can also give the diagram just in terms of the numbers of the statements. In the case of the serial argument above, the diagram looks like this: