A paradox is a self contradictory statement or situation. It's a logical process, in which the facts appear to be opposed to themselves. Paradox is a recognized philosophical tool for argument to assess groups of valid facts or logical processes which appear to be conflicting directly.
The problem with paradoxes is that each fact is known to be true. It can also relate to opinions, where the statement is based on an assertion. Paradoxes are solved by making logical connections between the facts, and identifying a logical process which applies to all facts.
In some cases, paradoxes are metaphors, and the metaphoric sense is the real issue in the paradox. In others, the paradox is a literal contradiction of actions or concepts.
Examples of paradox