Blurting vs Keeping

When my oldest daughter visits, her younger sister gets a little overwhelmed with the volume and speed of conversation she receives. She finally told her sister that there seems to be no holding place for her sister’s thoughts; they instantly come out. Her observation is true, my older daughter processes while she speaks and my younger daughter processes in her mind. My older daughter takes after me.

Sometimes I blurt out my thoughts and they are not formed well. They are in process and the lack of refinement results in raw bluntness. I read a Proverbs this morning that describes my speech as foolish.
Proverbs 12:23 (NIV)
The prudent keep their knowledge to themselves,
    but a fool’s heart blurts out folly.

I know I need to think before I talk instead of talking it out and then thinking. I want to be the wise person and not the fool. Why does the proverbs state that it is prudent to keep knowledge to yourself?  The New Living Translation helps make sense of this:
Proverbs 12:12 (NLT)
The wise don’t make a show of their knowledge,
    but fools broadcast their foolishness.

I am working on being wise with my voice and not foolish.
Do you blurt or do you keep your  knowledge until the proper time?

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