Any thing in existence is a sign of its creator and bears a signature of its maker. How can we believe that the dead, unconscious matter could have become alive by itself and without a life - giving source, start living so intelligently, as such inconceivably harmonious beings that our scientists with all their exhaustive research have been able to discover only a few fragments here & there about their hidden harmony and order.
And you can ask yourself: Can you believe a beautiful painting, could have been painted by itself? Can you easily ignore and rule out the need for a creative artist to create that beauty? Can you conceive of poetry with a significant composition of words without a poet!