There are trivial truths and the great truths. The opposite of a trivial truth is plainly false. The opposite of a great truth is also true.
The opposite of a fact is falsehood, but the opposite of one profound truth may very well be another profound truth.
The old saying of the two kinds of truth. To the one kind belongs statements so simple and clear that the opposite assertion obviously could not be defended. The other kind, the so-called 'deep truths', are statements in which the opposite also contains deep truth.
Truth is something that we can attempt to doubt, and then perhaps, after much exertion, discover that part of the doubt is not justified.
