There is a contradiction when we affirm something totally different and opposite to what we have expressed on the same issue before.
Affirm something different than what was said above
So, it will be a clear contradiction to say today that: We like Juan a few weeks ago when we commented about him that he is a person who we do not like how he behaves in every way.
Denial of what is claimed to be true
It will also be a contradiction denial of what is affirmed as true.
A) Yes, "Expressing that the president did not embezzle public funds when the court determined that he had done so will be a contradiction.”
Opposition between two issues
On the other hand, to the opposition between two issuesLikewise, it will be considered as a contradiction.
This is possible because two situations that pose differences in themselves will imply a contrast, an antagonism.
There are people who, because they have a tendency to be indecisive, can also be contradictory in their actions and thinking, because for example they want to buy a jean but they are not sure that it suits them, and then they choose to buy black pants.
Logic: antagonism between two premises
At the behest of the logic, which is the discipline that studies and evaluates the validity of the arguments in terms of the logical structure they present, a contradiction will imply the antagonism between two proposals.
In other words, for logic, the expressions “I'm hungry and I'm not hungry are a concrete contradiction.”
A typically human question of contradicting oneself
It should be noted that the contradiction is a typically human matter, strangely will belong to this world that individual who has never faced a contradiction in his life.
Because the contradiction is in some way the direct consequence of thinking, of human action, and because not also, in some exceptional cases, the consequence of a change in the way of thinking, which then generates that someone who thought something ten years ago already Do not think about it anymore, and even more, have an opinion that is completely opposite to the one you knew how to have in the past.
In many cases, the own evolution that people experience, or age growth, causes us to change our thoughts, opinions, among others, and this can cause us to confront in a contradictory way something that we held in the past but now no longer, and therefore, it can be seen as a contradiction for many people.
Although it is a typically human behavior as we already mentioned, people in general do not like them, we are uncomfortable with contradictions, and much more if they involve us in any way.
And this is so because there is a generalized belief that the contradiction that someone has regarding an issue, for example, before he was in favor of the adoption of children by homosexual couples and now he says not to be, keeps him from being a trustworthy person and credible, because basically one day he thinks one thing and tomorrow another about a topic, and people make noise, it makes them suspicious that their opinion on a topic can change so much, especially when it comes to sensitive issues such as those mentioned.
All of us contradict ourselves, we already said it, but in public personalities it is much more appreciable and notorious because their opinions are reflected in the mass media, and then thanks to the archive it is possible to find the contradiction of, for example, a politician about a theme.
And in the case of political leaders, normally, it becomes a matter of state, because the politician goes out of his way to achieve the credibility of the electorate.
Principle of contradiction: affirmation and negation cannot be true at the same moment
For his part, contradiction principle turns out to be a traditional law proposed by logic from which it is established that a argument and its negation can never be true at the same moment and in the same sense.
Throughout the history of philosophy, the question of this principle has been addressed, as all classical philosophers, such as: Aristotle, Plato, SocratesAmong the most notable, they have made reference to the issue of this incompatibility between two propositions that affirm and deny the same and even more, do it at the same time.
Never the same aspect can cover two things that are naturally opposed.
