# Are contradictory propositions in the propositional logic still contradictory in the predicate logic?

## What is the difference between predicate logic and propositional logic?

Propositional logic is the logic that deals with a collection of declarative statements which have a truth value, true or false. Predicate logic is an expression consisting of variables with a specified domain. It consists of objects, relations and functions between the objects.

Two propositions are contradictory iff they cannot both be true and they cannot both be false.

## What makes the proposition false?

This kind of sentences are called propositions. If a proposition is true, then we say it has a truth value of “true”; if a proposition is false, its truth value is “false”. For example, “Grass is green”, and “2 + 5 = 5” are propositions. The first proposition has the truth value of “true” and the second “false”.

## Is the contradictory the contrary?

As adjectives the difference between contrary and contradictory. is that contrary is opposite; in an opposite direction; in opposition; adverse while contradictory is that contradicts something, such as an argument.

## What is the difference between a proposition and a predicate propositional function )?

A predicate is a function. It takes some variable(s) as arguments; it returns either True or False (but not both) for each combination of the argument values. In contrast, a proposition is not a function. It does not have any variable as argument.

## What are the limitations of proposition logic How can we overcome that using predicate logic?

We can use propositional logic to validate the form of an argument that takes us from premises to a conclusion. We cannot use propositional logic to establish the truth of a proposition that isn’t given as a premise, or which can’t be inferred by the laws of inference.

## What is contradictory opposition of proposition?

Propositions are contradictory when the truth of one implies the falsity of the other, and conversely. Here we see that the truth of a proposition of the form All S are P implies the falsity of the corresponding proposition of the form Some S are not P.

## What is the difference between contrary and contradictory in logic?

Contradictories cannot at the same time be true nor at the same time false. Two statements are contrary to one another if they are both universals but differ in quality. Contraries cannot at the same time both be true, but can, at the same time, be false.

## Can two contradictory statements be true?

Contraries may both be false but cannot both be true. Contradictories are such that one of them is true if and only if the other is false.

## Is the relation that exists between propositions having the same subject and predicate but both propositions differ in quantity and quality?

Opposition: Occurs when two standard-form categorical propositions refer to the same subject and predicate classes, but differ in quality, quantity, or both.

## In which of the following propositions both can be true simultaneously but Cannot be false simultaneously?

Therefore, according to the relations given in the image, If two propositions are so related that both can be true simultaneously but cannot be false simultaneously are called – Subcontraries.

## When subject and predicate of both the premises are same but they differ in quantity only?

Sub alternation: Sub alternation opposition is the relation between two proposition having the same subject and predicate but differing in quantity only. The relation between universal negative (E) and particular negative (O) is called sub alternation.