Truth? Truth? There ain't no such animal.
Well, maybe, maybe not. Let's start with the assumption that that which can be proven with scientific objectivity can be safely placed in the category of "truth". Even this becomes problematic when further research uncovers previously unknown facts and older concepts must be laid to rest. Nevertheless, currently accepted scientific truths lend a level of reliability, confidence and comfort to decision-making.
Aristotle weighed in on the topic centuries ago when he said, "To say of what is that it is not, nor of what is not that it is, is false; while to say of what is that it is, and of what is not that it is not, is true." Which brings to mind Bill Clinton's question of how to define “is".
But, of course, much of our life is spent outside scientific validity, and this is where the rub comes in. Now it becomes a matter of truth by belief. We all believe what we want, choose or happen to believe. No one can gainsay or contradict the beliefs that one holds to be true. Whether right or wrong, adaptive or destructive, our beliefs are true for us. We are comforted when others believe as we do, just as we may be irritated by those who refuse to see the light.
So, this sets the stage for some philosophical considerations. Outside of science, is there such a thing as absolute truth? How can/should one examine an idea or concept for its truthfulness? Who or what do we take as an authority to lend credence to our beliefs?
What are the consequences of believing something that is not true? How would we know if we were in that situation? What consequences follow when our truths are contrary to those close to us, or to society in general?
If there is no absolute truth, how can we know the meaning of life? Why do we exist? What is this thing we call morality? If we cannot know the answer to these questions, is there any point in asking them? What difference does it make? How disconcerting is that!
There was once a bumper sticker that read, "God said it. I believe it. End of discussion."