Each concept is read twice: whether the approach carries it over, and whether the approach's own sources claim it. A concept that the approach claims but does not carry over is a shortfall. A concept that it neither claims nor carries over is an omission, which marks a gap in the field rather than a failure of the work.
Reasoning by Analogy
AbsentOmissionDefinition (Edward H. Levi, An Introduction to Legal Reasoning, 1949)
This procedure decides a new case by comparison with already decided ones. The judge states which features of the earlier case are relevant and which are not, and that selection is generally where the reasoning happens.
Analysis
The corpus is used once, as the input from which principles are extracted. No new case is then decided by comparison with earlier cases. The principles decide new cases instead.
Holding vs. Dicta
AbsentOmissionDefinition (Arthur L. Goodhart, 1930)
This distinction separates the part of a past decision that binds later cases (the holding) from the remarks made along the way (the dicta), which do not. Without a way to tell the two apart, a body of precedent cannot indicate which of its own decisions are actually binding.
Analysis
Preference records generally have no structure that separates what a judgment established from what was incidental to it. The induction treats all of it alike.
Distinguishing and Overruling
AbsentOmissionDefinition (Common-law practice)
These two techniques let a later court revise the record. Distinguishing confines an earlier precedent to its own facts, and overruling sets it aside altogether. Both are done openly and with reasons stated, which keeps a body of case law open to revision.
Analysis
The derivation from cases to rules runs once and then stops. After the principles are extracted, later cases generally cannot revise what earlier ones established. The result is a snapshot of the corpus at one moment rather than a record that stays open.
Paradigm Cases and Maxims
AbsentOmissionDefinition (Albert R. Jonsen & Stephen Toulmin, The Abuse of Casuistry, 1988)
This way of reasoning bases judgment on paradigm cases (i.e., clear cases on which agreement is easy) and on the short maxims drawn from them. A hard case is then settled by asking how far it is from the paradigms, rather than by deduction from a general principle.
Analysis
No case is singled out as a paradigm. Cases enter only in aggregate, as evidence for a principle.