The word "Buddha" means a person who has personally been able to perceive the ultimate truth. Buddha was considered "Siddhartha Gautam" before being recognized as the enlightened being. Most of the historians agree that his lifetime was between 563B.C. to 483B.C.
When we ignore such an inventory, we run the risk of citing platitudes allegedly bringing meaning and depth to our lives. We know what we believe but we don't know why. And when the why becomes increasingly obscure, so does the lived experience of the principle we hold to be true