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Self-explanitory. Different paragraphs are differnt quotes all from Nietzsche

Deception, flattering, lying, deluding, talking behind the back, putting up a false front, living in borrowed splendor, wearing a mask, hiding behind convention, playing a role for others and for oneself - in short, a continuous fluttering around the solitary flame of vanity - is so much the rule and the law among men that there is almost nothing which is less comprehensible than how an honest and pure drive for truth could have arisen among them.

The various languages placed side by side show that with words it is never a question of truth, never a question of adequate expression; otherwise, there would not be so many languages. The 'thing in itself' (which is precisely what the pure truth, apart from any of its consequences, would be) is likewise something quite incomprehensible to the creator of language and something not in the least worth striving for.
Every word instantly becomes a concept precisely insofar as it is not supposed to serve as a reminder of the unique and entirely individual original experience to which it owes its origin; but rather, a word becomes a concept insofar as it simultaneously has to fit countless more or less similar cases - which means, purely and simply, cases which are never equal and thus altogether unequal.

What then is truth? A movable host of metaphors, metonymies, and; anthropomorphisms: in short, a sum of human relations which have been poetically and rhetorically intensified, transferred, and embellished, and which, after long usage, seem to a people to be fixed, canonical, and binding. Truths are illusions which we have forgotten are illusions- they are metaphors that have become worn out and have been drained of sensuous force, coins which have lost their embossing and are now considered as metal and no longer as coins.

What is a law of nature as such for us? We are not acquainted with it in itself, but only with its effects, which means in its relation to other laws of nature - which, in turn, are known to us only as sums of relations. Therefore all these relations always refer again to others and are thoroughly incomprehensible to us in their essence. All that we actually know about these laws of nature is what we ourselves bring to them - time and space, and therefore relationships of succession and number. But everything marvelous about the laws of nature, everything that quite astonishes us therein and and seems to demand our explanation, everything that might lead us to distrust idealism; all this is completely and solely contained within the mathematical strictness and inviolability of our representations of time and space.

A work by Friedrich Nietzsche.

You see the simple definition of truth that it should be. Something is just... there and actually exists. However, from my deduction, Nietzsche sees no difference between truth and lies. The truth is merely what the human interprets whatever happened. It is not necessarily what happened, but how the human sees the event. Therefore, what is then the difference between a truth and lie, if humans see things differently? What is that fine line between pure truth and deceptions and lies?

Exactly... so... what is truth?

I would assume so. Even then... one should only believe half of what one sees... or so they say. ::shrugs::

Truth is an illusion.

Falsehood is deliberate contradiction in word/thought/deed of one's preception of reality (Their personal illusion).

Falsehood would be claiming to believe that which one does not.

Like saying you believe in God so the inquisitor doesn't hang you, even though you don't believe. Basically falsehood is lying.

Depends on whether you're an objectivist or not.

Existence obviously exists or there wouldn't be anyone percieving anything, much less anything to percieve.
So if it exists, most people would assume existence has concrete, unchanging properties that all people can sense in the same ways, but this isn't true. People percieve things differently based on their intelligence, position, past experiences, guiding values, etc.
People basically view the world through blinders, so even though an objective reality exists, most people cannot be expected to percieve it objectively.
Anyone can look around them and see that through direct observation atheism is the only "religion" with objective, empirical evidence, but this doesn't stop them from believing other theories because they want to believe them.

Everything that people believe/can believe is based on prior experience and "knowledge" they won't accept anything that can't fit through their seive that keeps out all the incongruous data.

Eh, it's late/early and I'm too tired to make sense, I'll try to sort this out tomorrow.