According to Dutilh Novaes (2020), deductive arguments have three main aspects, in order of greatest to least importance:
- Necessary truth-preservation – if the premises are true, then the conclusion is necessarily true. It follows from truth-preservation that deductive arguments are also monotonic; that is, if , then adding an arbitrary inference does not block the existing inference.
- Stepwise structure and perspicuity – the connection between premises and conclusion is clear in such a way that the truth of the premises guarantee the truth of the conclusion; this implies the property of transitivity. What is considered a “clear” connection depends on audience and context.
- Bracketing belief – reasoners only consider connections between premises and conclusions, not the content of either themselves.