| Application of a rule | Application of a Rule: Another variation of modus ponens is in the form of the application of a rule to things that satisfy a set of criteria: "rule X applies to any cases with characteristics A, B, C, and D. Individual case P has characteristics A, B, C, and D. Therefore, rule X applies to case P.
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| Argument | an argument is a group of propositions, some of which (called the premises) act as supporting evidence for another proposition (called the conclusion).
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| Arguments about the past based on present evidence | In these arguments, an inference is drawn about what happened at some earlier point in time based on current evidence. These are inductive arguments.
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| Arguments based on analogy | This argument rests on a comparison, from which it is claimed that a characteristic true of the one term in the equation will also be true of the other. In law this usually involves the application of a precedent or legal principle. These are inductive arguments.
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| Categorical form of a proposition | A proposition is called a categorical proposition if it can be expressed starting with the words All, No, Some, or x% (where x is any number other than 0 or 100).
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| Categorical syllogisms | These are three-line arguments (or chains of them), consisting of two premises and a conclusion, with all of the propositions in the form of categorical propositions.
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| Cause and effect reasoning | Here it is claimed that an event (effect) is based on one or more causal factors. Given the existence, then, of the causal factor(s), the effect should follow. These are inductive arguments.
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| Constructive dilemma | These take the form of: "If A then B, and if C then D. Either A or C is the case. Therefore, either B or D is the case." In other words, there's a choice between two options, where each option leads to some effect and you have to pick between either of the two options. This means, if you assume you'll pick one or the other option, then either of the two effects will happen.
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| Deductive | An argument in which the premises are said to offer sufficient support for the drawing of the conclusion. This means there are no missing pieces; that the evidence is all there backing up the conclusion. In that sense, a deductive argument is a closed set.
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| Disjunctive syllogism | These are arguments of the form: "Either A or B. Not A. Therefore, not B."
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| Hypothetical Syllogism | These are arguments of the form: "If A then B. If B then C. Therefore, if A then C."
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| Inductive | In an inductive argument the evidence alone is not enough for the conclusion to be certain, even if the premises are true. The evidence offers only partial support for the conclusion and, consequently, you cannot be certain that the conclusion is true.
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| Invalid argument | A deductive argument in which the premises, if true, do not guarantee the truth of the conclusion.
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| Modus Ponens | These are arguments of the form: "If A then B. A is the case. Therefore, B is true also."
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| Modus Tollens | These are arguments of the form: "If A then B. B is not the case. Therefore, A is not true either."
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| Predictions | In predictions, an argument is made about the future based on past or present evidence. A prediction is an inductive argument.
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| Proposition | A proposition is an assertion that is either true or false. A proposition can always be expressed in the form in which something (called the predicate) is either affirmed or denied about something else (called the subject). Stated differently: The subject designates the referent and the predicate the class of characteristics the subject does or does not share.
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| Sound argument | An argument that is both valid and has true premises. Only deductive arguments can be sound arguments. (not inductive arguments).
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| Standard Form | The standard form of a proposition is subject is/were/will be predicate.
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| Statistical reasoning | These arguments draw from sample studies or statistical reasoning, from which an inference then is drawn about either all or part of the targeted population.
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| Unsound argument | An argument that has one or both of these traits: (1) it is not valid, (2) it does not have true premises.
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| Valid argument | An argument in which the premises provide sufficient support for the conclusion, so if the premises were assumed to be true the conclusion could not be false. Only deductive arguments could be valid (not inductive arguments).
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