Philosophy 103Linguistics 103
Yet, still, Even further MoreIntroductory Logic: Critical Thinking
Dr. Robert Barnard
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Last Time:Laws of Thought: Philosophical Issues about the status of logical laws.MeaningTypes of Meaning: Cognitive/EmotiveIntension vs. ExtensionAmbiguity and PrecisionNames vs. Descriptions
Plan for TodayTalk about DefinitionsTime Permitting: Return to the issue of logical form
Definitions:Parts of a DefinitionDefiniendum: The word or term or concept to be definedDefiniens: the word or group of words which are used to define (assign a meaning to) another term or concept
Types of DefinitionsLexicalPrecisingTheoreticalPersuasive
A Lexical Definition reports or describes how a term is actually used in a language.
Sometimes a term has more than one definition.-
The Idea of a definitionidea (-d') n. Something, such as a thought or conception, that potentially or actually exists in the mind as a product of mental activity.An opinion, conviction, or principle: has some strange political ideas.A plan, scheme, or method.The gist of a specific situation; significance: The idea is to finish the project under budget.A notion; a fancy.Music A theme or motif.Philosophy In the philosophy of Plato, an archetype of which a corresponding being in phenomenal reality is an imperfect replica.In the philosophy of Kant, a concept of reason that is transcendent but nonempirical.In the philosophy of Hegel, absolute truth; the complete and ultimate product of reason.Obsolete A mental image of something remembered.
There are at least 3 specific philosophical definitions!!!
Precising DefinitionA Precising Definition is designed to reduce the vagueness of a term in use. This is a kind of stipulative definition.
Example: Tom is rich. (What does rich mean?)
we might extend the lexical definition by adding that here rich means has more than 5 million dollars. This makes the term PRECISE in our context.
Theoretical DefinitionA THEORETICAL DEFINITION assigns (stipulates) a meaning to a term by suggesting a theory that gives a certain characterization of the entities the theory denotes.
Theoretical definitions are common in mathematics and science. They fix the meaning of a term for a specific use.
Examples: Theoretical Definitions Geometry: Parallel straight lines are straight lines which, being in the same plane and being produced indefinitely in both directions, do not meet one another in either direction. (Euclid Elements I, Def 23)
Chemistry: An electron is a stable fundamental atomic particle with almost no mass and a negative charge.
A Persuasive Definition is a definition designed to produce a favorable or unfavorable emotional attitude toward whatever is denoted by the definiendum.
Persuasive definition relies upon both cognitive and emotive meaning. Since they exceed the scope of cognitive meaning, persuasive definitions are primarily rhetorical.
Persuasive Definition ExamplesNeutral Definition:
Abortion: In medicine, an abortion is the premature exit of the products of conception (the fetus, fetal membranes, and placenta) from the uterus. It is the loss of a pregnancy and does not refer to why that pregnancy was lost.
Unfavorable Emotive attitude definition:Abortion: The willful murder of innocent unborn children, often performed to avoid the personal and societal consequences of wanton sexual activity.Favorable Emotive attitude definition:Abortion: The constitutionally protected act of medically resolving a pregnancy for the purpose of restoring, preserving or protecting the physical or mental health of a woman. The procedure is especially useful in protecting women from potentially debilitating consequences of rape and incest.
Some Tools for Developing DefinitionsPoint to a case of the Definiendum (ostention)Specify the INTENSION of the term.Enumerate (in part or whole) the EXTENSION of the term.Make the term precise by tracing its place in a taxonomy.
Ostensive (pointing) DefinitionBy Dog I mean: By Flux Capacitor I mean:
Definition by IntensionHere we indicate the characteristics or qualities that the definiendum connotes.
Square: regular figure on a Euclidian plane bounded by four sides of equal length and four right angles.
Fish: cold-blooded, aquatic vertebrates, with gills, commonly fins, and often an elongated body covered with scales.
Definition by Enumeration (extension)
Even numbers: 2, 4, 6, 8, 10, 12, 14, 16
Blue: the common feature of blueberries, the sky on a clear day, some peoples eyes, the ocean in some places,
Taxonomic Definition by Genus and DifferentiaThis sort of definition relies upon the fact that our concepts are often related by being more or less general. We have broad terms for general types and then other words for specific sub-types or case sunder the general heading. The GENUS is the general typeThe DIFFERENTIA is the characteristic that marks a specific sub-class or case.A Genus and Differentia together define a SPECIES.
Genus and Definition Examples
TermGenusDifferenceDAUGHTER=Offspring+FemalePUPPY=Dog+ YoungSTUDENT=Person+ Enrolled in SchoolICE= Water+FrozenPRESIDENT=Political Leader+ AmericanHOUSE=Structure+Free-standing , Permanent, ResidentialSOCRATES= Human Being+ Teacher of Plato
Definitions and MeaningsSome terms have meaning which we record or report with a lexical definition.Some terms have more than one meaning, we use precising definition to stipulate which meaning is relevant.Some terms are given meaning by a definition (ostensive, enumerative, theoretical)Some definitions contain emotive content that can be confused with cognitive content.
NEW TOPIC: LOGICAL FORM
Good vs. Bad ArgumentsDeductive Validity IF the premises are true THEN the conclusion MUST be true.Inductive Strength IF the premises are true THEN the conclusion WILL BE PROBABLE.Deductive Soundness the deductive argument is valid AND premises are all trueInductive CogencyThe inductive argument is strong and the premises are all true
Deduction and Argument FormIn order to talk about validity we need to come back to the idea of an argument form.Form is the STRUCTURE of the argument.The Structure can either be good or bad. It can either do its job or not.A good structure will allow the premises to support the conclusion.
Review: Standard Form of an ArgumentSample Argument: Socrates is mortal because all men are mortal
Standard form isolates conclusion and lists ALL premises.All men are mortal (given premise)Socrates is a man (implied premise)Socrates is mortal. (Conclusion)
Logical Form of an Argument Determining Logical FORM:If Al likes Sally then Al will ask Sally out
Al likes Sally
Therefore Al will ask Sally out
If -- P -- then -- Q--
Therefore -- Q --We Determine FORM by isolating the logical structure of the argument.
Another example of logical form[R] Every school teaches religion and religious beliefs. This can be seen by the fact that either a school is religious or not. And if it isnt it either teaches a form of secular humanism or teaches atheism by teaching nothing. Both humanism and atheism therefore teach specific beliefs about religion.
Isolate Conclusion FIRSTEvery school teaches religion and religious beliefs. This can be seen by the fact that either a school is religious or not. And if it isnt openly religious then it either teaches a form of secular humanism or teaches atheism by teaching nothing. Both humanism and atheism therefore teach specific beliefs about religion.
LIST PREMISESThis can be seen by the fact that either a school is religious or not. And if it isnt openly religious then it either teaches a form of secular humanism or teaches atheism by teaching nothing. Both humanism and atheism therefore teach specific beliefs about religion.Every school teaches religion and religious beliefs.
CLARIFY PREMISES1. Every school is openly Religious or not-openly Religious. 2. If a school is not openly religious then it either teaches secular humanism or teaches atheism by teaching nothing. 3. Both humanism and atheism are specific beliefs about religion.SO 4. Every school teaches religion and religious beliefs.
Add in an obvious assumed premiseEvery school is openly Religious or not-openly Religious. All openly Religious schools teach religion and religious beliefs3. Both humanism and atheism are specific beliefs about religion. (re-ordered).4. If a school is not openly religious then it either teaches secular humanism or teaches atheism by teaching nothing. SO
5. Every school teaches religion and religious beliefs.
SUBSTITUTE FOR TERMSIf S(chool) then R(eligious) or not-R. If R, then T(eaches religion)If not-R then H (teach humanism) or A (teaches atheism) (old 4 moved up)4. If H then T and If A then T
5. Every S is T
ClarifyIf S then (R or not-R). If R, then TIf not-R then (H or A) (If H then T) and (If A then T)
5. If S then T (re-stated if x then y = all x are y
Issues!!!Is the form valid?Is the analysis here correct? (Is Religious belief the same as belief about religion?)Are the premises true (soundness?)
Validity and FormKEY POI