Happiness consists in movement--the brain is ultimately designed for action.  We reflect on incoming information:  What does this mean?  How does it connect to what is already known and recognized?  How can I categorize/ identify/ name this?

Once we "know" what it means or what it is called, the executive center of the brain takes over to determine action/ planning:  What do I do with this information?  How do I use if (for survival/ advancement/ growth?  Once the plan is formed, the motor center of the brain acts, and we receive feedback, or new information about our deduced meaning and plan. 

As we move, or act, we discover new things along the way, and that discovery brings pleasure.

So God continually calls us forward, "out of the empty way of life lived by your fathers" (Romans, I think).  We move on Abraham's journey from what we already know/ are used to/ toward what we cannot guess, what we do not know.  We move toward discovery, delight in the revelation of the new:  "Morning by morning, you open my ears to hear your word/ instruction/ revelation"  (have to locate the reference).

We are designed to move forward; it is when we refuse to move, when we are afraid to move, when we are stuck in all we "know" that we are unhappy, for the past has us chained to itself.   God's path for us is a journey of constant discovery and delight, of breaking free from what holds us bound.