Example of an argument outline

This argument can be found in the beginning of Immanuel Kant's Prolegomena to any Future Metaphysics.

Conclusion:

Pure natural science is possible only insofar as the“categories” thought by the understanding provide the objective conditions for all possible objects of experience.

Premises:

1. Pure natural science does not concern the existenceof objects in themselves (35/294).

a. The existence of actual objects can only be determined through experience.

b. Experience is excluded from pure natural science, insofar as the latter is a prioriand lawful.

c. Experience is the domain of contingent, actually existing objects, although the conditions of the possibility of experience are universal and necessary (36/296).

2. Nature is the object of judgments of perception and of experience.

a. Judgments of perception are only subjectively valid, for there is no necessity attaching to these.

b. Judgments of experience are objectively valid, because they are based on the pure concepts of the understanding (38/298).

3. The conditions for pure natural science are what make judgments of experience possible.

4. Judgments of experience are based on the pure concepts of the understanding, which are known as the “categories.”