It all comes down, I think, to how you define "truth". There are different "truths". To me, what we imperfectly call "truth" falls into two main classifications: objective truth and intersubjective truth. An example of objective truth would be, for example, the effects of gravity. Gravity exists. It's measurable, quantifiable, and is easily proven. If you doubt it, throw a rock straight up into the air and wait. The truth of gravity will be proven to you very quickly. Intersubjective truth is a tougher nut to crack. These are the truths that I believe you're implying. They have to do with an agreed on worldview that a group of people share. The most obvious examples would probably get me in trouble. A safe example might be "Honesty is the best policy." Lots and lots of people would agree on this old saying and, if you asked them, they would say that it's absolutely true. But is it? Does believing that it's true make it true? Is it quantifiable? Is it measurable? In the end, isn't it just and unproveable idea, rather than a "truth"? Whew. That's pretty heavy for first thing in the morning. My head hurts. Truth !