Logic 101

I miss studying in the university.

My mind was challenged

ngayon its stagnating.

Sigh.

At dahil naghahalungkat ako ng books 

mula sa baul ng kalat sa bahay.

Nakita ko ang Logic Book ko.

Madami din akong natutunan lalo na ang

isa sa mga life philosophy ko.

Na-realize ko na lang ito ng pina-define sa amin ang truth.

This is my version of truth, that there isn't one,

because truth is one's version of fact.

There is no one truth kumbaga, 

it all depends on the perspective.

(walang kokontra gawa-gawa ko lang yan

hindi ako philosopher or logician hahaha)

This is why I tend to take time in deciding,

I look for the pros and cons.

Neutral muna bago ang lahat para makapag-isip.

Ano nga ba ang basics ng Logic,

magbalik tanaw tayo.

(cue guni-guni music at blurry bokeh effect)

(Image Source)

Logic: the study of the methods and principles used to distinguish correct reasoning from incorrect   reasoning.

Propositions: something that maybe asserted or denied; refer to what  declarative sentences are typically used to assert.

Inference: process by which one proposition is arrived at and affirmed on the basis of one or more other propositions accepted as the starting point of the process.

Argument: any group of propositions of which one is claimed to follow from the others, which are regarded as providing support or grounds for the truth of that one

Conclusion:  proposition that is affirmed on the basis of the other propositions of the argument, and these other propositions, which are affirmed or assumed as providing support or reasons for accepting the conclusion, are the Premises of that argument.

Common conclusion-indicators:

• therefore - for these reasons
• hence - it follows that
• thus - we may infer
• so - I conclude that
• accordingly - which shows that
• in consequence - which entails that
• consequently - which entails that
• proves that - which implies that
• as a result - which allows us to infer that
• for this reason - which points to the conclusion that

Common premiss-indicators:

• since - as indicated by
• because - the reason is that
• for - for the reason that
• as - may be inferred from
• follows from  - may be derived from
• as shown by - may be deduced from
• inasmuch as - in view of the fact that

Deductive Argument: is valid when its premiss, if true, do provide conclusive grounds for the truth of its conclusion; one whose conclusion is claimed to follow from its premiss with absolute necessity , this necessity not being a matter of degree and not depending  in any way on whatever else may be the case.

Inductive Argument: one whose conclusion is claimed to follow from its premiss only with probability, this probability being a matter of degree and dependent upon what else may be the case.

Three Basic Functions of Language:

• To communicate information
• Expressive function
• Directive function

Three Kind of Disputes:

• Obviously genuine dispute - in which the parties explicitly and unambiguously  disagree either in belief or in attitude.
• Merely verbal dispute - there is no genuine disagreement between the parties at all and yet there appears to be disagreement.
• Apparently verbal but really genuine - when the parties misunderstand one another's use of terms.

Five Kinds of Definition:

• Stipulative Definition - arises from the deliberate assignment of a meaning
• Lexical Definition - reports a meaning the defiendum already has; if the term being described is not new but has an established usage to eliminate ambiguity.
• Precising Definition - serve to reduce vagueness
• Theoretical Definition - attempts to formulate a theoretically adequate or scientifically useful description of the objects to which the term applies.
• Persuasive Definition - used to resolve disputes by influencing the attitudes or stirring the emotions of readers or hearers.

Denotation/Extension: general term or class term, denotes the several objects to which it may corrcetly be applied.

Connotation/Intension: The set of attributes shared by all and only those objects to which the term refers.

Rules for Definition:

• Should state the essential attributes of the species.
• Must not be circular.
• Must be neither too broad nor too narrow.
• Must not be expressed in ambiguous, obscure or figurative language.
• Should not be negative where it can be affirmative.