The truth may be out there, but lies are inside your head.

The words of Terry Pratchett—“The truth may be out there, but lies are inside your head”—strike with paradoxical clarity, clothed in wit yet heavy with meaning. He reminds us that truth, though sometimes distant and hidden, exists independently of us. It lies in the fabric of the world, waiting to be sought, discovered, and embraced. But lies, unlike truth, do not need to be sought—they are born within us, whispered by our fears, our pride, and our desires. They take root in the mind, shaping perception, until we mistake illusion for reality. Thus, the greatest enemy is not the distant truth we have yet to find, but the inward lies that blind us from seeing it.

This teaching recalls the wisdom of the ancients. Plato spoke of the prisoners in the cave, who saw only shadows upon the wall and mistook them for reality. The shadows were not cast by the world outside, but by their own captivity of perception. So too does Pratchett warn us: the truth is outside the cave, shining with the light of the sun, but the lies we carry inside prevent us from turning toward it. We are often not defeated by ignorance of the world, but by the deceits we weave in our own hearts.

History too testifies to this. Consider the tragedy of the Trojan War. The Trojans were offered a gift: a wooden horse. The truth—that it was a trap—was visible to those who questioned. Cassandra, cursed though she was, spoke it. Yet the Trojans were ensnared not by the Greeks’ cunning alone, but by the lies inside their own heads: pride that told them they could not be deceived, and hope that whispered the war had ended. These inward lies blinded them to the truth standing before their very gates, and thus a mighty city fell.

Or look to the modern world, where propaganda and misinformation spread. Lies succeed not merely because they are told, but because they take root in the soil of human thought. A lie repeated becomes familiar, and familiarity feels like truth. People embrace it not because the world has changed, but because their minds have been shaped to accept the false as real. Thus, as Pratchett teaches, lies are inside your head—for it is the mind that nurtures them, feeds them, and gives them power.

But there is hope, for the truth is out there. Though it may be hidden, it is unchanging, waiting to be uncovered. The task, then, is to quiet the inward noise of lies so that the outward truth may be heard. This requires humility—to admit that we may be deceived. It requires courage—to face truths that may be uncomfortable. And it requires discipline—to seek evidence, to listen deeply, and to test what we believe. Only in this way can the inward lies be silenced, and the outward truth be embraced.

The lesson for us is this: guard your thoughts, for the battlefield of truth is not only in the world, but within the mind. Question your assumptions. Do not accept every whisper of pride or fear as truth. Seek the voices of others, weigh them against reality, and never be afraid to change when the truth reveals itself. Lies thrive in silence and unexamined thoughts, but they wither in the light of inquiry.

Therefore, O seeker, remember: truth is eternal, but lies are personal. The world will not bend to our illusions, but our illusions will blind us from the world. Let us strive, then, to cleanse our minds of inward falsehood, so that when we search outwardly, we may see clearly. For the truth may indeed be out there—but unless we conquer the lies within, we shall never find it.