# Basic Logic: Arguments with Unnecessary Premise

## What can an argument with false premises be?

A 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.

## What are the 4 types of arguments in logic?

Different Types Of Arguments: Deductive And Inductive Arguments

• Type 1: Deductive Arguments.
• Type 2: Inductive Arguments.
• Type 3: Toulmin Argument.
• Type 4: Rogerian Argument.

## Can you have an argument without a premise?

An argument without premises is a single sentence : the conclusion. if and only if it is true under every possible interpretation of the language. In propositional logic, they are tautologies.

## What is false premise in logic?

A false premise is an incorrect proposition that forms the basis of an argument or syllogism. Since the premise (proposition, or assumption) is not correct, the conclusion drawn may be in error. However, the logical validity of an argument is a function of its internal consistency, not the truth value of its premises.

## Do all premises need to be true?

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.

## Can a logical argument be false?

Logical fallacies are flawed, deceptive, or false arguments that can be proven wrong with reasoning. There are two main types of fallacies: A formal fallacy is an argument with a premise and conclusion that doesn’t hold up to scrutiny.

## What is an example of a valid argument with a false conclusion?

If Elizabeth Taylor is president of the United States, then Elizabeth Taylor must be younger than 35. Elizabeth Taylor is president of the United States. So, Elizabeth Taylor must be younger than 35. For either example, the logic is valid but the premises are false.

## Can a valid argument have false premises example?

If Elizabeth Taylor is president of the United States, then Elizabeth Taylor must be 35 years of age or older. Elizabeth Taylor is president of the United States. So, Elizabeth Taylor must be 35 years of age or older. For either example, the logic is valid but the premises are false.

## What is a defect in an argument other than its having false premises?

A fallacy is a defect in an argument other than its having false premises. It refers to a defect that is difficult to be detected. An informal fallacy is a defect in the content of an argument.

## What is an example of an invalid argument?

An argument is said to be an invalid argument if its conclusion can be false when its hypothesis is true. An example of an invalid argument is the following: “If it is raining, then the streets are wet. The streets are wet.

## What is an invalid argument in logic?

Invalid: an argument that is not valid. We can test for invalidity by assuming that all the premises are true and seeing whether it is still possible for the conclusion to be false. If this is possible, the argument is invalid.

## Can deductive arguments have false premises?

A deductive argument can have false premises and a true conclusion.

## Is an argument with contradictory premises valid?

Well, if the premises are contradictory, then they cannot all be true (that’s just what contradictory means) so they can’t all be true while the conclusion is false (the necessary condition for non-validity). So the argument cannot be non-valid, it must be valid. Thus an argument with contradictory premises is valid.

## Do all arguments have to have more than one premise?

There can be one or many premises in a single argument. A conclusion is a statement in an argument that indicates of what the arguer is trying to convince the reader/listener. What is the argument trying to prove? There can be only one conclusion in a single argument.

## How many premises does an argument need?

two

In logic, an argument requires a set of (at least) two declarative sentences (or “propositions”) known as the “premises” (or “premisses”), along with another declarative sentence (or “proposition”), known as the conclusion.

## How many premises can there be in an argument?

Arguments can have any number of premises (even just one) and sub-conclusions. Often arguments have unstated premise(s), that is, premise(s) that need to be added for the premises to support the conclusion. It’s always instructive to try to state all the premises necessary to support one’s conclusion.