An argument is valid when all the inferences are tight and all the premises are interlocking. The accepted terminology is that deductive arguments are valid if the acceptance of the premises necessarily entails the conclusion. In contrast to a topical outline, the logical outline seeks only to present arguments and points of contention. The logical outline, in contrast, is not a summary. Any other material, such as classificatory remarks and various enumerations, is omitted from the logical outline. Outlining is a process by which the reader reconstructs the presentation of the premises so that they entail the conclusion. A logical outline is different from the style of a topical outline, which is the outline most of us were taught. There are two recognized argument types: deductive argument, in which the conclusion follows necessarily from the premises, and inductive argument, in which the conclusion follows contingently from the premises.