If a child can get this, why can't we?
One day a 6 year old girl was sitting in a classroom where the teacher was going to explain evolution to the children. 
The teacher asked a little boy name Tommy... "Tommy do you see the tree outside?" 
Tommy said "Yes." 
The teacher then asked "Tommy, do you see the grass outside?" 
And Tommy again said "Yes"
The teacher said "Tommy, go outside and look up and see if you can see the sky."
Tommy said "Okay,"  and a few minutes later he returned and said "Yes, I saw the sky." 
The teacher then said, "Did you see God? " to which Tommy said "No!"
The teacher exclaimed "That's my point. We can't see God because he isn't there. He doesn't exist!"
Then a little girl spoke up and said "Teacher, may I ask Tommy some questions?"
The teacher agreed and told her to proceed.
The little girl said, "Tommy, do you see the tree outside?"
Tommy answered "Yes."
The little girl then asked, "Tommy do you see the grass outside?" 
Tommy, getting tired of the questions by this time said, "Yessssss!!!"
The little girl asked Tommy, "Well did you see the sky?" 
Tommy again answered, "Yessssss!!!"
The little girl said, "Now Tommy, do you see the teacher?" 
And Tommy said "Yes."
The little girl then asked, "Do you see her brain?"
Tommy said, "No!" 
The little girl said, "Then according to what we were taught today in school, she must not have one!
The lesson to be learned???
"FOR WE WALK BY FAITH, NOT BY SIGHT" ( 2 Corinthians 5:7)