Ultimate Truth is the guiding light. It's worth aiming for. It's worth it to be a good person. It is worth trying to figure out the difference between right and wrong. This is just common sense. If I'm a mean person, and I hurt people, I'm not going to have a peaceful coexistance with the rest of humanity. Call it a mixture of utilitarian, mystical and relativistic nonsense. I'm nothing other than a summation of my experiences somehow existing in a cohesive form and trying desperately to understand what that means.
Lacanians call it The Real, Buddhists call it Śūnyatā, and Freemasons call it the Absolute Truth of the Great Architect. All of these and many other philosophical, mystical, religious and spritual organizations are some sort of positive reflection on Ultimate Truth. Whatever the hell that means.
I'm not particularly interested in spending much time pondering the meaning of Ultimate Truth in a direct manner. I'd rather approach the subject by writing a song about trains or doing the dishes.
Like Icarus, if you fly too close to the sun, your man-made wings of wax will melt and leave you plummeting to your doom.