Something that has the character of truth by necessity or as a result of absolute certainty. Much of Western philosophy includes the requirement of apodictic security, but since the second half of the nineteenth century, this requirement has been called into question.
The best that human research can get to is relative truth, which is much less apodictic certainty.
Our transience and infallibility, it seems, will forever leave us behind the kind of truth or security that figures such as Plato, Aristotle, Descartes, and Hegel have sought. Accepting this does not mean embracing skepticism, but rather embracing fallibilism.