Principles of definition:
-defining terms (definiens) must be clearer and more familiar than the term to be defined
-defining terms must be different and entirely different from term to be defined: no repetition of definiendum, no synonyms, no etymologically or derivationally related terms (circularity)
-positive statement where possible: definiens must meet criteria of concision and inclusion, not the possibly infinite criteria of exclusion; note problem of defining negative concepts
Test of definition:
-is the definiens essential? Can it be inverted with the definiendum?
e.g.: Man <=> "rational animal," BUT Man <¹> "biped animal"
Parts of definiens: definiendum = genus + differentia
Kinds of differentia: "material, formal, efficient, and final"
e.g.: table = "furniture" (genus) + "made by carpenter" (efficient) + "wood" (material) + "four legs, flat top, etc." (formal) + "used to serve food, do work, etc." (final)
Extended description: genus + properties (essential) + accidents (secondary) +comparisons, illustrations, etc.
Deliberative discourse: the study of what is worthy or worthless in itself, or of that which is advantageous or injurious to others.
The three modes of deliberative discourse: appeal to reason, to feelings, or to character and moral authority. "Reason" can be deductive, using syllogism or enthymeme, or inductive, using probability. Induction allows the following projection from the known to the unknown: ("=>" means "entails") " If A => B => C => D, and A’ => B’ => C’, then D’ is also probably true." When A/A’... are of the same order of being, then the prediction of D’ is ordinary induction; when they are of different orders of being, it is called analogy.
Common topics and sub-topics: choosing the thesis statement, "something to say".
Definition: genus (±true of genus => ±true of species)
division (do the parts make up the whole? what can be eliminated?)
Comparison: similarity (are both terms of the same order of being?)
difference (in kind or degree)
Relationship: cause and effect
antecedent and consequent (i.e., the major premisse of the syllogism)
contraries vs. contradictions (cf. "the square of oppositions")
Circumstance: the possible and impossible
1) if one of a pair of contraries is possible, so is the other
2) if one of a pair of similars is possible, so is the other
3) if the more difficult of two things is possible, the less difficult is too
4) if something can have a beginning, it can have an end; if it can have an end, it must have had a beginning
5) if the parts are possible, so is the whole, and conversely
6) if a thing can be produced with neither art nor preparation, it can be produced with them
past and future fact
1) if the less probable has occurred, so will the more probable
2) if B follows A, and B has occurred, so has A (and conversely)
3) given that the power, the desire, and the opportunity for A to happen were present, then A has happened
4) given the power, desire, and opportunity now for A to happen, then it will
5) given the antecedents, the natural consequence will occur
Testimony: authority, anecdotes, statistics, maxims, laws, precedents and examples...