Logic test 1

arguments 2 parts

1- one or more statement (premises) offering evidence in support of the truth (conclusion) 2- The conclusion whose truth is said to be supported by the presmise

Are some deductive arguments have true premises and yet be invalid

A deductive argument is said to be valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false. Otherwise, a deductive argument is said to be invalid.

are some deductive arguments are invalid and yet have a true concision

A deductive argument is said to be valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false. Otherwise, a deductive argument is said to be invalid.

Syllogism

A form of deductive reasoning consisting of a major premise, a minor premise, and a conclusion.

Can an argument be true or false?

Arguments are NOT true/false; they are valid or sound.

can an argement be invalid but still have a true conclusion

FALSE: It is possible for an invalid argument to have all true premises and a true conclusion.

defintion of declarative sentence

expresses a claim thats either true or false

defintion- exclamatory sentence

expresses an emotion or feeling not T/F

Can an invalid argument contain true premises

f an argument is invalid, then it must have at least one false premise. If an argument has a conclusion that is certainly false, then the argument must be invalid. If the premises and conclusion are all false, the argument must be invalid. Some invalid arguments have true premises and a true conclusion.

implication

if frist is true then second is true

logiclly inconsitant

if it not possible they are all true

what is a premise

indicators

sound argument

is argument that is valid and whose premises are all true

hypothesis testing

make and test an educated guess about a problem/solution

what are the common deductive forms

math and defintional

inductive logic

method for evaluation inductive reasoning

generalization from a sample

premises present in formation about a sample of algae group

defintion- interrogatory sentence

questions, not true or false

defintion of inductive reasoning

shows NOT that the conclusion is True

defintion of deductive reasoning

shows conclsuion must be TRUE

What is a non-argument?

stories, questions, commands

cogent agrument

strong and prem are all true

Defintion Argument

termed used in logic, genrally is reasoning that has been put into words

contingent statement

truth or false depending on its cogent changing circumstances

definition- performative sentence

use an action not T/F

can an valid argument have false premises

valid argument can have false premises; and it can have a false conclusion. But if a valid argument has all true premises, then it must have a true conclusion. ... Since a sound argument is valid, it is such that if all the premises are true then the conclusion must be true.

Modus Ponens

If A, then B A Therefore, B

Modus Tollens

If P then Q Not Q Therefore not P

Can a valid argument have a false conclusion?

If a valid argument has a false conclusion, then at least one premise must be false

all invalid arguments have false premise

If an argument is invalid, then it must have at least one false premise. If an argument has a conclusion that is certainly false, then the argument must be invalid. If the premises and conclusion are all false, the argument must be invalid. Some invalid arguments have true premises and a true conclusion.

Can an invalid argument have true premises

So if a valid argument does have a false conclusion, it cannot have all true premises. Thus at least one premise must be false. ... If an invalid argument has all true premises, then the conclusion must be false

can an invalid argument have a true conclusion

So if a valid argument does have a false conclusion, it cannot have all true premises. Thus at least one premise must be false. ... If an invalid argument has all true premises, then the conclusion must be false. FALSE: It is possible for an invalid argument to have all true premises and a true conclusion.

are some sound arguments have false premises

TRUE: A valid argument cannot have all true premises and a false conclusion.

can a deductive argument have false premises and a false conclusion and be valid nether-less

TRUE: A valid argument cannot have all true premises and a false conclusion. So if a valid argument does have a false conclusion, it cannot have all true premises. Thus at least one premise must be false

are some arguments have true premises and are also valid

TRUE: A valid argument cannot possibly have all true premises and a false conclusion

all sound arguments have true premises and are also valid

TRUE: If an argument is sound, then it is valid and has all true premises.

analogical argument

The argument lists the characteristics that two (or more) things have in common and concludes that the things being compared probably have some other characteristic in common

prediction agrument

a claim about the duture is made based upon facts from past

unsound argument

a deductive argument that is invalid, has one or more false premises, or both

Disjunctive Syllogism

a syllogism in which the major premise includes two or more mutually exclusive alternatives

what is categorial syllogism

always a sentence, that relate 2 categories of things by assuming that, all, non or some of 1 categories

logical consistancy

any possibility no matter how unlikely, remote, or improbable that they are true

defintion- imperative sentence

commands true or false, not declarative

agrument from authority

concludes something that is true on the grounds that an authority on the matters say its true

Hypothetical Syllogism

conditional, "if P then Q"