The pragmatic argument is a first-order predicate argument that supports a policy with a fact (1 pre PF).
ANALYSIS OF AN EXAMPLE
Children should not sleep with artificial night-lighting, because this leads to myopia
The arguer states in the conclusion that a certain activity should not be carried out and supports this claim by stating that the activity leads to myopia. Since the argument fits the form a is X, because a is Y, it can be identified as a first-order predicate argument. In this specific case, a is instantiated by ‘children sleeping with artificial night-lighting’, X is instantiated by ‘should not happen’, and Y is instantiated by ‘leads to myopia’.
Children sleeping with artificial night-lighting (a) should not happen (X), because children sleeping with artificial night-lighting (a) leads to myopia (Y)
First-order predicate arguments are further differentiated by identifying the types of statement in the conclusion and the premise. In this case, the former is a statement of policy and the latter a statement of fact, which means that we are dealing with a first-order predicate argument supporting a policy with a fact (1 pre PF).
The trivial name of first-order predicate arguments is derived from the characterization of the relationship between the predicates X and Y. In this example, the undesirable consequences of the activity, that it leads to myopia (Y), functions as a reason for advising that it should not happen (X). Traditionally, such an argument is called a ‘pragmatic argument’.