Midterm Notes

TERMS

A term is a written or spoken word expressing a concept or an idea. Or it is a sensible conventional sign expressive of an idea.

Explanation of definition
1. Sensible- what can be perceived by the senses.
2. Conventional- arbitrary, settled by agreement.
3. Sign – something that manifests another thing aside from itself.

Classification of terms

I. According to Meaning
1. Univocal or homologous: Term bearing the same meaning as applied to several individuals. The Greek original homology denotes same meaning.

2. Analogous: Term expressing kindred meaning. The Greek original analogy means associated meaning. It may be analogous:

a) by proportion, or by association of the objects to which the term is applied. Thus, e.g., the term healthy is analogous by proportion, when applied to a man as subject of health, to climate as a factor, and to color as a sign of health.
b) By proportionality, or by virtue of kindred similarity of conceptual and formal reasons denoted (metaphysical analogy). E.g. the 1/3 of 27 and the 1/3 of 9: the former is 9, and the latter is only 3.
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4. Equivocal: Term outwardly or apparently the same, bur expressing different meanings. The Latin original equivocal denotes sameness as to term only. The term may be equivocal:

a) In pronunciation only. E.g.: sweet and suite; week and weak; sun and son; hens and hence; In Hiligaynon: Mayo and mayo( as month and as good), tu-od and tu-od (as true and as a protruding something).
b) In writing only. E.g., bow(bou) and bow(bo) (inclination or weapon);
c) Both in pronunciation and writing. E.g.: ball(round and dance); bat(animal and club); club(weapon and group); butt(a thick end of anything and a push delivered by the head).

5. Metaphorical: Term transferred from its proper meaning or object and applied to something else, on account of the latter’s resemblance to the former and to denote that resemblance. E.g.: the King of animals, henpecked husband, tomboy; hand of God, School head.


II. According to Quality:

a) Positive: Term that expresses a formal reason of a thing proper. E.g., life ; plants; love; tall; being; substance.
b) Negative: Term that expresses the absence of something or its lack of perfection. E.g., nothing; poverty; ugly; blindness; death.


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Other divisions of term are according to comprehension, components, function, relation and object which we do not consider with great practical usage.

THE PREDICAMENTS AND PREDICABLES

What are they?

The predicaments are classifications of universal natures and concepts. Whereas, the predicables are classification of universal predicates in general. Predicaments are useful in giving order into our universal concepts by way of classification.

The Supreme Predicaments

Aristotle called them categories, which is Greek term for Predicaments. According to Aristotle there are two Supreme Predicaments: that of substance and that of accident. Substance is a being that carries existential reality by itself. Accident is a modification of the substance and does not carry existential reality by itself.

The Ten Predicaments

The first predicament is that of substance; the remaining nine are the sub-classifications of the predicament accident:

1) Substance: A nature that carries existential actuality by itself and not as inhering in something else. E.g., a tree , an animal, table, chair , chalk.
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2) Quantity: Modification of substance as having extended and measurable parts. This with regards to dimension and weight. E.g. 140 lbs; 6’ 2” tall, 5 fingers.
3) Quality: A formal modifier of the substance( health, figure, beauty, color, etc.) E.g. Sexy body; blue eyes, white lady, dangerous enemy.

4) Relation: Reference of one substance to another. Eg., motherhood or mother, friend, kinship, mentor.

5) Action: motion of the substance, commonly inducing result in another thing. E.g., running, sawing ,playing, hitting, flying.

6) Passion: Modification of a substance as a result of another agent. E.g., a wound , a contusion.

7) When: Circumstantial determination as to time or duration. E.g., at noon, at dawn, at three o’clock.

8) Where: Circumstantial determination as to place. E.g, In Bacolod , on your knee, in your stomach.

9) Posture: Determination of the substance as top disposition of the parts. E.g., Standing. lying, upright.

10) Habit: Determination of the substance as to external outfit. E.g., armed, dressed up, tatttoed, bespectacled.

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DEFINITION

Definition discloses the formal or conceptual comprehension of an object. Division discloses the formal and conceptual extension of an object. Hence, Definition and Division were called by ancient Logicians ways of knowing.

Definition is the conceptual manifestation either of the meaning of a term, or of the formal features of an object.


Definitions may be:

1. Nominal definition – is the synonymous or equivalent term or its etymology or word origin E.g. : Sow or a female pig; philosopher or lover of wisdom.
2. Real definition – is the conceptual manifestation of a thing by its objective features or reasons. E.g.: microscope is an optical instrument designed to magnify the image of minute objects; a house is a structure for human dwelling.


RULES

1. The definition must be clearer than the thing to b defined.
2. The definition must not contain the term or feature to be defined.
3. The definition must be positive as must as possible.
4. The definition must be adequate.

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DIVISION

Logical division is the conceptual manifestation of the inferiors of the universal, or of parts of an object, by way of an orderly and comprehensive enumeration of them.

RULES

1. The division must be adequate, that is, the parts taken together must equal to the whole, and must not be more or less. Hence:

A. All parts must be enumerated. The following is wrong: Substances are animals and men. The Filipinos are the Ilocanos, the Tagalogs and the Visayans.

B. No part may exceed the whole. Hence, the following is wrong: University of St. La Salle Has the following colleges: CAS, CBA, Nursing, Engineering, Education, Medicine, Law and Architecture.

C. No part may equal the whole. Hence the following is wrong: College of Arts and Sciences Comprises the following departments: Masscom, IDS, Languages, Philosophy, Religious Studies, P.E., social Sciences and CAS Family.


D. Nothing must be included as part which is not a true part. the following is wrong: Negros is composed of Negros Occidental, Negros Oriental and Siquijor.

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2. The division must be clear.
A. It must be reasonably limited.
B. There should be one basis for division.

3. The members of the division must be mutually exclusive; otherwise they would not all be different parts as presented to be. The following is wromng: The religious denominations I the Philippines are Catholics, Protestants, Buddhists, Muslims and sects
4. The division must be orderly, that is, it must be done first by the immediate members or parts, and so on.

THE PROPOSITION

The proposition is the mental manifestation of the mental pronouncement. Or simply it is a statement which affirms or denies something. The Logical proposition is differentiated from ordinary sentence in the following points;

1. The logical Proposition is expressed in the Indicative Mood.
2. The logical Logical Proposition is expressed in the present tense.
3. The predicate of the logical proposition should be separately expressed from the bonding verb is, otherwise such objective identity or non-identity is not properly expressed.

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ELEMENTS OF THE PROPOSITION

The subject and predicate are called the matter of the proposition, because they are the materials out of which the proposition is made. The copula or bonding verb is called the form, because it is the unifying principle that maintains the structure o0f the proposition and imparts to its material the nature of the proposition.

It should be noted that the Subject, or the Predicate may be compound term, or a term with a dependent clause 9complex term) E.G.: “The student you introduced to me” is “the most intelligent in their class.”

KINDS OF PROPOSITIONS

1. Categorical Proposition is one that express a positive, or a negative judgment in an absolute manner. E.G.: La Salle is an academic institution; Negros is an island; Silaynons are not stingy; No Bacolodnon is a senator. Faculty members are not happy with their salary; Paul is faithful and strong.

2. Hypothetical Proposition is one that does not express an absolute judgment, but a qualified one. E.G.: If you fail in Philosophy one, you will not graduate; A student is either honest or dishonest.


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The basis of the truth of the conditional proposition is the dependence of the consequent on the Antecedent; and the lack of
it , is the basis of its falsehood. E.g.: If one has a cellular phone,
then he has easy access to communication – true. If one has easy access to communication, then he has a cellular phone – false.

3. Disjunctive proposition is one that expresses alternatives, all of which cannot be together true, or together false; but only one is true with the exclusion of the rest. E.g.: Either whales are mammals or they are large fish; It is either male or female.

KINDS OF CATEGORICAL PROPOSITIONS

A. Simple categorical proposition is divided according to: 1. Quality 2. Quantity 3. Quality and Quantity

1. Quality:
1.1. Affirmative- is a proposition which expresses the objective identity of the subject with the predicate: Catholics are Christians; Non-Christians are the majority in the world; Ecumenism is a movement; Pre-marital sex is a sin;
1.2. Negative – is a proposition which expresses the objective non-identity of the subject with the predicate. E.G.: Parents are not adversaries; No student is stupid.

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2. Quantity:
2.1. Universal – is a proposition that covers all its extension, or all its inferiors distributively. E.g.: All Negrenses are Visayans.
2.2. Particular – is a proposition where the subject expresses only parts of the universal. E.g.: Some students are intelligent-looking.
2.3. Singular – is a proposition wherein the subject expresses a specific individual. E.g.: Gil P. is a professor.

3. Quantity and Quality:

3.1. Universal-Affirmative – is designated by the symbolic letter “A”, E.g.: All Faculty members are college graduates.
3.2. Particular-Affirmative – is designate by the symbolic letter “I”. E.g.: Some parents are irresponsible.
3.3. Universal-Negative – is designated by the symbolic letter “E”. E.g.: No mother is a male.
3.4. Particular- Negative – is designated by the latter “O”. E.g.: Some drivers are drunkards.

The symbolic letters are taken from the Latin verbs: AffIrmo (I affirm) and nEgO (I deny).

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OPPOSITION

Opposition is the disagreement or difference of two propositions having the same subject and the same predicate, as regards Quality, Quantity or both. This is illustrated in the “Square of opposition” given below:

A- All men truthful O- All men are not truthful


A CONTRARY O
C Y
O R
N O
T T
R C
A I
SUB-ALTERN D SUB-ALTERN
A I
R C
T T
N O
O R
C Y
I SUB-CONTRARY O

I- Some men are truthful Some men are not truthful- O

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KINDS OF OPPOSITION

A. Contradictory propositions are those that have the same subject and the same predicate; but differ in quantity and quality. E.g.: All Bacolodnons are Negrenses – Some Bacolodnons are not Negrenses; No philosopher is insane – Some philosophers are insane.
Rule: If one proposition is true, the other is false; the other false.

B. Contrary propositions are those that have gthe same subject ansd same predicate and universal extension; but differ in quality. E.g: All Bacolodnons are Negrenses – All Bacolodnons are not Negrenses; No Philosopher is insane –Philosopher is insane.
Rule: If one contrary proposition is true, the other is false. If one is false the other is doubtful.
C. Sub-contrary propositions are those that have the same subject and the same predicate and the same particular extansion; but differin in quality,. E.g.: Some Bacolodnons are Negrenses – Some Bacolodnons are not Negrenses; Some philosophers are not insane – Some philosophers are insane.
Rule: If one sub-contrary proposition is false, the other is true. If one is true, the other is doubtful.

D. Sub-altern propositions are those that have the same subject, same predicate and quality; but differ as to quantity. E.g.: All Bacolodnons are Negrenses – Some Bacolodnons are Negrenses; Some philosophers are not insane – Philosophers are not insane.
Rule: If the universal subaltenant is true, then the particuklar subalternate is also true; because the truth of the universal is also the

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truth of the particular but not vice-versa. If the universal subaltenant is false; then the universal subalternant is also false; but not vice-versa.



A fallacy is a component of an argument that is demonstrably flawed in its logic or form, thus rendering the argument invalid in whole, except in the case of begging the question, a false analogy and other informal fallacies. In logical arguments, fallacies are either formal or informal. Because the validity of a deductive argument depends on its form, a formal fallacy, or logical fallacy is a deductive argument that has an invalid form, whereas an informal fallacy is any other invalid mode of reasoning whose flaw is not in the form of the argument.
Beginning with Aristotle, informal fallacies have generally been placed in one of several categories, depending on the source of the fallacy. There are fallacies of relevance, fallacies involving causal reasoning, and fallacies resulting from ambiguities. A similar approach to understanding and classifying fallacies is provided by argumentation theory.

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Recognizing fallacies in actual arguments may be difficult since arguments are often structured using rhetorical patterns that obscure the logical connections between assertions. As we illustrate with various examples, fallacies may also exploit the emotions or intellectual or psychological weaknesses of the interlocutor. Having the capability of recognizing logical fallacies in arguments will hopefully reduce the likelihood of such an occurrence.
A different approach to understanding and classifying fallacies is provided by argumentation theory; see for instance the van Eemeren, Grootendorst reference below. In this approach, an argument is regarded as an interactive protocol between individuals which attempts to resolve a disagreement. The protocol is regulated by certain rules of interaction and violations of these rules are fallacies. Many of the fallacies in the list below are best understood as being fallacies in this sense.

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Contents

• 1 Aristotelian fallacies
• 1.1 Material fallacies
• 1.2 Verbal fallacies
• 1.3 Logical fallacies
• 2 Other systems of classification
• 3 Fallacies in the media and politics
• 4 General list of fallacies:
• 5 General examples
• 5.1 Example 1: Material Fallacy
• 5.2 Example 2: Verbal Fallacy
• 5.3 Example 3: Verbal Fallacy
• 5.4 Example 4: Logical Fallacy
• 6 See also
• 7 References
• 8 External links

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Aristotelian fallacies

Material fallacies

The classification of material fallacies widely adopted by modern logicians and based on that of Aristotle, Organon (Sophistici elenchi), is as follows:
• Fallacy of Accident (also called destroying the exception or a dicto simpliciter ad dictum secundum quid) meaning to argue erroneously from a general rule to a particular case, without proper regard to particular conditions that vitiate the application of the general rule; e.g. if manhood suffrage be the law, arguing that a criminal or a lunatic must, therefore, have a vote.
• Converse Fallacy of Accident (also called reverse accident, destroying the exception, or a dicto secundum quid ad dictum simpliciter) meaning to argue from a special case to a general rule.
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• Irrelevant Conclusion (also called Ignoratio Elenchi), wherein, instead of proving the fact in dispute, the arguer seeks to gain his point by diverting attention to some extraneous fact (as in the legal story of "No case. Abuse the plaintiff's attorney"). The fallacies are common in platform oratory, in which the speaker obscures the real issue by appealing to his audience on the grounds of
• purely personal considerations (argumentum ad hominem)
• popular sentiment (argumentum ad populum, appeal to the majority)
• fear (argumentum ad baculum)
• conventional propriety (argumentum ad verecundiam)
This fallacy has been illustrated by ethical or theological arguments wherein the fear of punishment is subtly substituted for abstract right as the sanction of moral obligation.


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• Begging the question (also called Petitio Principii or Circulus in Probando--arguing in a circle) consists in demonstrating a conclusion by means of premises that pre-suppose that conclusion. Jeremy Bentham points out that this fallacy may lurk in a single word, especially in an epithet, e.g. if a measure were condemned simply on the ground that it is alleged to be "un-English".
• Fallacy of the Consequent, really a species of Irrelevant Conclusion, wherein a conclusion is drawn from premises that do not really support it.
• Fallacy of False Cause, or Non Sequitur (L., it does not follow), wherein one thing is incorrectly assumed as the cause of another, as when the ancients attributed a public calamity to a meteorological phenomenon (a special case of this fallacy also goes by the Latin term post hoc ergo propter hoc; the fallacy of believing that temporal succession implies a causal relation).


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• Fallacy of Many Questions (Plurium Interrogationum), wherein several questions are improperly grouped in the form of one, and a direct categorical answer is demanded, e.g. if a prosecuting counsel asked the defendant " What time was it when you met this man? " with the intention of eliciting the tacit admission that such a meeting had taken place. Another example is the classic line, "Is it true that you no longer beat your wife?"

Verbal fallacies

Verbal fallacies are those in which a conclusion is obtained by improper or ambiguous use of words. They are generally classified as follows.
• Equivocation consists in employing the same word in two or more senses, e.g. in a syllogism, the middle term being used in one sense in the major and another in the minor premise, so that in fact there are four not three terms ("All heavy things have a great mass; This is heavy fog; therefore this fog has a great mass").

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• Amphibology is the result of ambiguity of grammatical structure, e.g. of the position of the adverb "only" in careless writers ("He only said that," in which sentence, as experience shows, the adverb has been intended to qualify any one of the other three words).
• Fallacy of Composition is a species of Amphibology that results from the confused use of collective terms. e.g. "The angles of a triangle are less than two right angles" might refer to the angles separately or added together.
• Division, the converse of the preceding, which consists in employing the middle term distributively in the minor and collectively in the major premise.
• Proof by verbosity, sometimes colloquially referred to as argumentum verbosium - a rhetorical technique that tries to persuade by overwhelming those considering an argument with such a volume of material that the argument sounds plausible, superficially appears to be well-researched, and it is so laborious to untangle and check supporting facts that the argument might be allowed to slide by unchallenged.

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• Accent, which occurs only in speaking and consists of emphasizing the wrong word in a sentence. e.g., "He is a fairly good pianist," according to the emphasis on the words, may imply praise of a beginner's progress, or an expert's depreciation of a popular hero, or it may imply that the person in question is a deplorable violinist.
• Figure of Speech, the confusion between the metaphorical and ordinary uses of a word or phrase.

Logical fallacies

The standard Aristotelian logical fallacies are:
• Fallacy of Four Terms (Quaternio terminorum)
• Fallacy of Undistributed Middle
• Fallacy of Illicit process of the major or the Illicit minor term;
• Fallacy of Negative Premises.
In philosophy, the term logical fallacy properly refers to a formal fallacy : a flaw in the structure of a deductive argument which renders the argument invalid.

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However, it is often used more generally in informal discourse to mean an argument which is problematic for any reason, and thus encompasses informal fallacies as well as formal fallacies. – valid but unsound claims or bad nondeductive argumentation – .
The presence of a formal fallacy in a deductive argument does not imply anything about the argument's premises or its conclusion (see fallacy fallacy). Both may actually be true, or even more probable as a result of the argument (e.g. appeal to authority), but the deductive argument is still invalid because the conclusion does not follow from the premises in the manner described. By extension, an argument can contain a formal fallacy even if the argument is not a deductive one; for instance an inductive argument that incorrectly applies principles of probability or causality can be said to commit a formal fallacy.

Other systems of classification

Of other classifications of fallacies in general the most famous are those of Francis Bacon and J. S. Mill. Bacon (Novum Organum, Aph.

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33, 38 sqq.) divided fallacies into four Idola (Idols, i.e. False Appearances), which summarize the various kinds of mistakes to which the human intellect is prone. With these should be compared the Offendicula of Roger Bacon, contained in the Opus maius, pt. i. J. S. Mill discussed the subject in book v. of his Logic, and Jeremy Bentham's Book of Fallacies (1824) contains valuable remarks. See Rd. Whateley's Logic, bk. v.; A. de Morgan, Formal Logic (1847) ; A. Sidgwick, Fallacies (1883) and other textbooks.

allacies in the media and politics

Fallacies are used frequently by pundits in the media and politics. When one politician says to another, "You don't have the moral authority to say X", this could be an example of the argumentum ad hominem or personal attack fallacy; that is, attempting to disprove X, not by addressing validity of X but by attacking the person who asserted X. Arguably, the politician is not even attempting to make an argument against X, but is instead offering a moral rebuke against the interlocutor. For instance, if X is the assertion:

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The military uniform is a symbol of national strength and honor.
Then ostensibly, the politician is not trying to prove the contrary assertion. If this is the case, then there is no logically fallacious argument, but merely a personal opinion about moral worth. Thus identifying logical fallacies may be difficult and dependent upon context.
In the opposite direction is the fallacy of argument from authority. A classic example is the ipse dixit—"He himself said it" argument—used throughout the Middle Ages in reference to Aristotle. A modern instance is "celebrity spokespersons" in advertisements: a product is good and you should buy/use/support it because your favorite celebrity endorses it.
An appeal to authority is always a logical fallacy, though it can be an appropriate form of rational argument if, for example, it is an appeal to expert testimony. In this case, the expert witness must be recognized as such and all parties must agree that the testimony is appropriate to the circumstances. This form of argument is common in legal situations.

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By definition, arguments with logical fallacies are invalid, but they can often be (re)written in such a way that they fit a valid argument form. The challenge to the interlocutor is, of course, to discover the false premise, i.e. the premise that makes the argument unsound.

General list of fallacies:

Common logical fallacy examples:
• formal fallacies
• Argument from fallacy "ad logicam"
• Affirming the consequent or Denying the antecedent
• Faulty generalization Inductive fallacies like
• Biased sample
• Hasty generalization (also called fallacy of insufficient statistics, fallacy of insufficient sample, fallacy of the lonely fact, leaping to a conclusion, hasty induction, secundum quid)
• Misleading vividness
• Package-deal fallacy or False dilemma (also called false dichotomy or bifurcation)

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• Questionable cause Informal causal fallacies (also called non causa pro causa)
• Begging the question, circular logic "petitio principii"
• Correlation implies causation "Cum hoc ergo propter hoc"
• Post hoc ergo propter hoc
• Appeal to consequences "ad consequentiam"
• Appeal to force "Ad baculum"
• Appeal to probability & Slippery slope
• Informal Relevance fallacies
• Irrelevant conclusion "Ignoratio elenchi" like Red Herring
• Straw man
• Association fallacy & Guilt by association
• Ad hoc
• Argument from ignorance, incredulity, belief, conviction... "ad ignorantiam"
• Appeal to emotion like Appeal to fear, Appeal to flattery, Appeal to pity, Appeal to spite...

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• Wishful thinking
• Appeal to authority or Appeal to ridicule "Ad hominem"
• Appeal to the majority "ad populum"
• Appeal to tradition "ad antiquitatem"
• Informal Verbal fallacies
• Equivocation like Loki's Wager
• Undistributed middle & No true scotsman
For a concise list of "appeal to" fallacies, see Appeal (disambiguation).
General list of fallacies: The entries in the following list are neither exhaustive nor mutually exclusive; that is, several distinct entries may refer to the same pattern. As noted in the introduction, these fallacies describe erroneous or at least suspect patterns of argument in general, not necessarily argument based on formal logic. Many of the fallacies listed are traditionally recognized and discussed in works on critical thinking; others are more specialized.
• Appeal to novelty (also called argumentum ad novitatem)

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• Argument from silence (also called argumentum ex silentio)
• Appeal to wealth (also called argumentum ad crumenam)
• Appeal to poverty (also called argumentum ad lazarum)
• Argument from repetition (also called argumentum ad nauseam)
• Base rate fallacy
• Conditional probability fallacy
• Conjunction fallacy
• Continuum fallacy (also called fallacy of the beard)
• Correlative based fallacies including:
• Fallacy of many questions (also called complex question, fallacy of presupposition, loaded question or plurium interrogationum)
• Denying the correlative
• Suppressed correlative
• Definist fallacy
• Dicto simpliciter, including:

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• Accident (also called a dicto simpliciter ad dictum secundum quid)
• Converse accident (also called a dicto secundum quid ad dictum simpliciter)
• Fallacies of distribution:
• Composition
• Division
• Ecological fallacy
• False analogy
• False attribution
• False premise
• False compromise
• Faulty generalization including:
• Gambler's fallacy/Inverse gambler's fallacy
• Genetic fallacy
• Historian's fallacy
• Homunculus fallacy
• If-by-whiskey (argues both sides)
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• Inappropriate interpretations or applications of statistics including:
• Screening test fallacy
• Incomplete comparison
• Inconsistent comparison
• Invalid proof
• Judgmental language
• Juxtaposition
• Lump of labour fallacy (also called the fallacy of labour scarcity)
• Meaningless statement
• Middle ground (also called argumentum ad temperantiam)
• Naturalistic fallacy
• Negative proof
• Non sequitur like Affirming the consequent, also including its opposite
• Perfect solution fallacy
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• Poisoning the well
• Proof by assertion
• Proof by verbosity (also called argumentum verbosium)
• Questionable cause (also called non causa pro causa) including:
• Fallacy of the single cause
• Joint effect
• Regression fallacy
• Texas sharpshooter fallacy
• Wrong direction
• Reification (also called hypostatization)
• Relativist fallacy (also called subjectivist fallacy)
• Restricted Universalism, Fallacy of
• Retrospective determinism (it happened so it was bound to)
• Shifting the burden of proof
• Special pleading
• Style over substance fallacy
• Sunk cost fallacy
• Syllogistic fallacies, including:
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• Affirming a disjunct
• Affirmative conclusion from a negative premise
• Existential fallacy
• Fallacy of exclusive premises
• Fallacy of four terms (also called quaternio terminorum)
• Illicit major & Illicit minor

[edit] General examples
Fallacious arguments involve not only formal logic but also causality. Others involve psychological ploys such as use of power relationships between proposer and interlocutor, appeals to patriotism and morality, appeals to ego etc., to establish necessary intermediate (explicit or implicit) premises for an argument. Indeed, fallacies very often lay in unstated assumptions or implied premises in arguments that are not always obvious at first glance. One way to obscure a premise is through enthymeme.
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We now give a few examples illustrating common errors in reasoning. Note that providing a critique of an argument has no relation to the truth of the conclusion. The conclusion could very well be true, while the argument itself is not valid. See argument from fallacy.
In the following, we view an argument as a dialogue between a proposer and an interlocutor.

Example 1: Material Fallacy
James argues:
1. Cheese is food.
2. Food is delicious.
3. Therefore, cheese is delicious.
This argument claims to prove that cheese is delicious. This particular argument has the form of a categorical syllogism. Any argument must have premises as well as a conclusion. In this case we need to ask what the premises are, that is the set of assumptions the proposer of the argument can expect the interlocutor to grant. The
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first assumption is almost true by definition: cheese is a foodstuff edible by humans. The second assumption is less clear as to its meaning. Since the assertion has no quantifiers of any kind, it could mean any one of the following:
• All food is delicious.
• Most food is delicious.
• To me, all food is delicious.
• Some food is disgusting.
In all but the first interpretation, the above syllogism would then fail to have validated its second premise. James may try to assume that his interlocutor believes that all food is delicious; if the interlocutor grants this then the argument is valid. In this case, the interlocutor is essentially conceding the point to James. However, the interlocutor is more likely to believe that some food is disgusting, such as a sheep's liver white chocolate torte; and in this case James is not much better off than he was before he formulated the argument, since he now has to prove the assertion that cheese is a unique type of universally delicious food, which is a disguised form
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of the original thesis. From the point of view of the interlocutor, James commits the logical fallacy of begging the question.

[edit] Example 2: Verbal Fallacy
Barbara argues:
1. Andre is a good tennis player.
2. Therefore, Andre is 'good', that is to say a morally good person.
Here the problem is that the word good has different meanings, which is to say that it is an ambiguous word. In the premise, Barbara says that Andre is good at some particular activity, in this case tennis. In the conclusion, she says that Andre is a morally good person. These are clearly two different senses of the word "good". The premise might be true but the conclusion can still be false: Andre might be the best tennis player in the world but a rotten person morally. However, it is not legitimate to infer he is a bad person on the ground there has been a fallacious argument on the
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part of Barbara. Nothing concerning Andre's moral qualities is to be inferred from the premise. Appropriately, since it plays on an ambiguity, this sort of fallacy is called the fallacy of equivocation, that is, equating two incompatible terms or claims.

Example 3: Verbal Fallacy
Ramesh argues:
1. Nothing is better than eternal happiness.
2. Eating a hamburger is better than nothing.
3. Therefore, eating a hamburger is better than eternal happiness.
This argument has the appearance of an inference that applies transitivity of the two-placed relation is better than, which in this critique we grant is a valid property. The argument is an example of syntactic ambiguity. In fact, the first premise semantically does not predicate an attribute of the subject, as would for instance the assertion
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A potato is better than eternal happiness.
In fact it is semantically equivalent to the following universal quantification:
Everything fails to be better than eternal happiness.
So instantiating this fact with eating a hamburger, it logically follows that
Eating a hamburger fails to be better than eternal happiness.
Note that the premise A hamburger is better than nothing does not provide anything to this argument. This fact really means something such as
Eating a hamburger is better than eating nothing at all.
Thus this is a fallacy of composition.

Example 4: Logical Fallacy
In the strictest sense, a logical fallacy is the incorrect application of a valid logical principle or an application of a nonexistent principle:
1. Some drivers are men.
2. Some drivers are women.
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3. Therefore, some drivers are both men and women.
This is fallacious. And so is this:
1. The average family has 2.5 children.
2. The Smiths are a very average family.
3. therefore, the Smiths must have 2.5 children.
Indeed, there is no logical principle that states
1. For some x, P(x).
2. For some x, Q(x).
3. Therefore for some x, P(x) and Q(x).
An easy way to show the above inference is invalid is by using Venn diagrams. In logical parlance, the inference is invalid, since under at least one interpretation of the predicates it is not validity preserving.

See also
• Attacking Faulty Reasoning
• Anecdotal evidence
• Apophasis
• Cogency
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• Cognitive bias
• Demagogy
• Fallacy
• Fallacies of definition
• False statement
• Informal logic
• Invalid proof
• Paradox
• Sophism
• Soundness
• Spurious relationship
• Validity
• Vacuous truth

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