Thats not true. If the "how" is proven to have never occured, neither did the "why". for example, lets say science conclusively proves the "great flood" never ocurred. "Why" becomes irrellevant.
If you ask me "
HOW is the sky blue?"...and my response is; "because particulate matter in the upper atmosphere filters out all the color spectrum of light but blue".
If you ask me "
Why is the sky blue?"...my response would be..."
Why isn't it blue on Mars?"