What an awesome question, Linda, and an interesting article! I feel that there are different kinds of "truth." We can't ever be privy to all actual truths, but the open mind is one that really desires truth. A locked mind simply wants to be "right!" The examples you illustrated, like your sons' room and the oak, are perfect examples of this. As is the religious question...
Your sons each wanted to be right, and each had created a "reality" based on a portion of truth...but each had the same goal in mind...to get out of cleaning! In the end, they both walked away feeling as if their "truth" had served them. Had they each been open to the actual truth, which was they were both responsible for the mess, they would have been in touch with your goal, which was of course, a clean room! With the effort they both put into making the room clean again, they would have walked away with the sense of common unity and self worth...instead of their isolated feelings of separation from each other and you. From the truth.
I feel that the lies people nourish in their minds are far more easy to digest and accept than the truth...because they are comforting. The ego is happy, they get to be right, and don't have to face the humility of being...*GASP*....WRONG! LOL! But, in reality...the Emporor still had no clothes, regardless of what he believed the truth to be.
Truth sometimes hurts, but all important lessons do. For me, I would rather be hurt by truth than by lies! Humility is such an important feeling...it nurtures humbleness and openness to the world around you, and lists you as one part of the whole, instead of the center of it. While lies can be charming, they are separating influences, and serve only the person who creates them.
For religion, the actual truth is, you will never know the truth, therefore, *it doesn't matter.*