Logic 102

At dahil mahaba-haba ang primer ko patungkol sa Logic,

gumawa ako ng part 2 mwahahaha.

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Fallacy: is a type of argument that may seem to be correct, but that proves on examination not to be so.

Fallacies of Relevance: rely on premisses that may seem to be relevant to the conclusion but in fact are not.

• Argument from Ignorance (ad ignorantiam) - a proposition is true on the ground that it has not been proved false or vice versa.
• Appeal to inappropriate authority (ad verecundiam) - the premisses of an argument appeal to the judgement of some party or parties having no legitimate claim to authority in the matter at hand.
• Argument against the person (ad hominem) - an attack is leveled not at the claims being made or the merits of the argument but at the person of the opponent.
• Appeal to emotion (ad populum) - careful reasoning i sreplaced with devices calculated to elicit enthusiasm and emotional support for the conclusion advanced.
• Appeal to pity ( ad misericordiam) - careful reasoning is replaced by devices to elicit symnpathy on the part of the hearer for the objects of the speaker's concern.
• Appeal to force (ad baculum) - careful reaoning is replaced with direct or insinuated threats to bring about the acceptance of some conclusion.
• Irrelevant conclusion (ignoratio elenchi) - premisses miss the point, purporting to support one conclusion while in fact supporting or establishing another.

Fallacies of Presumption: mistaken arguments arise from reliance upon some proposition that is assumed to be true, but is in fact false or dubious, or without warrant.

• Complex question  - asked in such a way as to presuppose the truth of some assumption buried in that question.
• False cause - when one treats as the cause of a thing what is not really the cause of that thing; when one blunders in reasoning that is based upon causal relations.
• Begging the question (petitio principii) - one assumes the premisses of an argument the truth of what one seeks to establish in the conclusion of that argument.
• Accident - when one applies a generalization to an individual case that it does not properly govern.
• Converse accident - when one moves carelessly or too quickly from a single case to an indefensibly broad generalization.

Fallacies of Ambiguity: formulated in such a way as to rely on shifts in the meaning of words or phrases, from their use in the premisses to their use in the conclusion.

• Equivocation - when the same word or phrase is used with two or more meanings, deliberately or accidentally in the formulation of an argument.
• Amphiboly - when one of the statements in an argument has more than plausible meaning, because of the loose or awkward way in which the words in that statement have been combined.
• Accent - a shift of meaning arises within an argument as a consequence of changes in the emphasis given to its words or parts.
• Composition - committed when one reasons mistakenly from the attributes of a part to the attributes of the whole and when one mistakenly reasons from the attributes of an individual member of some collection to the attributes of the totality of that collection.
• Division - committed when one reasons mistakenly from the attributes of a whole to the attributes of one of its parts or when one reasons mistakenly from the attributes of the individual entities within that collection.

Four Basic Standard-Form Categorical Propositions:

• A propositions - universal affirmative
• I propositions  - particular affirmative
• E propositions - universal negative
• O propositions - particular negative