This is a quote from Albert Einstein, and it is missing a word. There is also more to the quote:
The most beautiful things we can experience is the mysterious. It is the source of all true art and all science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead: his eyes are closed.
By this, I believe Einstein meant that there is beauty in the mysteries of the universe and of humankind. He is telling us to slow down, observe, appreciate, and having done so, to solve the mysteries, find the patterns, explain the behavior of our world and ourselves. This is what art and science are meant to do. A good example, looking back in history, is Charles Darwin. He found beauty in the natural world around him and contemplated its mysteries. He was open to new ideas. His finding the beauty in the mysterious led to the theory of evolution. And I do think no matter how many mysteries we solve, there will be more mysteries and more beauty for us to stand "rapt in awe."