Logic is the technique by which we add conviction to truth.
The French moralist Jean de la Bruyère, whose words were sharp as a chisel against the stone of human vanity, once declared: “Logic is the technique by which we add conviction to truth.” In this teaching, he reminds us that truth, though eternal, often lies hidden in silence or obscured by passion. It exists whether men believe in it or not, but to make truth shine, to give it weight in the hearts and minds of others, we require the art of logic—that disciplined method which orders thought, clears confusion, and strengthens the foundation of conviction.
Truth is like a diamond buried deep in the earth: indestructible, yet unseen. Logic is the tool by which we cut away the soil, polish the stone, and set it before the eyes of mankind. Without logic, truth may be dismissed as mere opinion, a whisper drowned by the noise of doubt. With logic, truth becomes undeniable, clothed in reason so that even the skeptic must bow. Thus La Bruyère places logic not above truth, but as its servant, giving it armor and sword with which to prevail in the battles of thought.
History shows us how this principle unfolds. Consider Socrates, who walked the streets of Athens asking questions that seemed simple but were in fact blades of logic. The sophists could proclaim anything and call it true, but when Socrates led them step by step through reasoning, their falsehoods collapsed. He did not invent truth—he revealed it. By logic, he added conviction to truth, and even those who condemned him to death could not erase the power of his reasoning, which endures to this day.
So too with Abraham Lincoln, who during the dark days of America’s Civil War defended the truth of liberty and equality. Many men already felt those truths stirring in their souls, but Lincoln gave them form through arguments rooted in history, law, and plain reason. His speeches did not merely declare truth—they convinced. The Gettysburg Address, in fewer than three hundred words, used the discipline of logic to transform grief into purpose, reminding a nation why it must endure. He proved La Bruyère’s wisdom: logic binds conviction to truth, so that truth is not only known but also followed.
Yet there is also a warning in this saying. For if logic is the technique that strengthens truth, then corrupted logic can also strengthen falsehood. Men have used clever reasoning to disguise lies, persuading multitudes by appearances of order. Thus, we must remember that logic without truth is a weapon of deception. La Bruyère speaks of its noblest use—when it becomes the servant of truth, not the slave of ambition. Logic must polish the diamond, not carve false jewels to mislead the eye.
The lesson for us is clear: love truth, but also cultivate logic, for truth alone is not always enough to convince the world. You must learn to reason, to order your thoughts, to speak with clarity and precision. Do not think of logic as cold or lifeless; think of it as the fire that hardens the blade of truth until it can cut through ignorance and doubt. Truth is eternal, but logic is the force that plants it in the hearts of men.
Practical wisdom must follow. Train yourself in reasoning: question assumptions, follow arguments to their root, and learn to separate passion from principle. When you defend truth, do not rely only on emotion, for feelings fade; use the strength of clear thought, so that your words endure. And when you hear an argument, test it with logic, to see whether it carries truth or only the disguise of it. By such practice, you will become a defender of truth who cannot be shaken.
Thus, remember La Bruyère’s teaching: logic gives conviction to truth. Truth is the eternal flame, but logic is the lamp that carries it through the darkness. Without it, truth may remain unseen; with it, truth becomes a beacon that guides nations, inspires souls, and withstands the assaults of time.
MTNguyen Minh Tu
I’m struck by how this quote positions logic as a tool to affirm truth, but not necessarily as the source of it. Does this mean that logic, in itself, isn’t always the best way to understand truth? Could emotions, intuition, or experience be equally valid methods of finding truth, especially when logic doesn’t fully align with those personal or subjective understandings?
HHuyen
This quote makes me think about how often we rely on logic to explain things to others, as if logic is the ultimate form of persuasion. Does that mean that truth, without logical backing, is less valid or less believable? How do we balance emotional truths with logical arguments? I wonder if there are truths that logic can’t fully capture or explain.
YNPham Ngoc Yen Nhi
Jean de la Bruyère’s idea that logic adds conviction to truth is intriguing because it seems to elevate logic as a persuasive force. But does that mean that a truth without logic is less convincing, or harder to accept? What happens when two truths clash, and each is backed by different logical arguments? Does logic always strengthen truth, or can it be used to distort it?
TNTra Nguyen
This quote reminds me of how often we try to apply logic to things that aren’t always logical, like emotions or subjective experiences. Is it possible that by using logic, we sometimes try to force truths into neat boxes, even when they might be more complex or ambiguous? Can truth ever truly be ‘proven’ with logic, or is it something more abstract that we feel deep down?
LAPham Lan Anh
I find this quote interesting because it suggests that logic doesn’t create truth, but rather reinforces it. It makes me wonder—does truth always require logic to be convincing? Can something be true even if it doesn’t follow a logical argument? It seems like Jean de la Bruyère is implying that logic is a tool to help us accept and understand truth, rather than being the creator of truth itself.