An atheist once asked Imaam Shaafi‘ee (rahimahullah) to prove the existence of the creator, Allah Ta‘ala. Imaam Shaafi‘ee (rahimahullah) answered, “Look at the leaves of the mulberry tree. The color, taste, smell, composition and properties of every leaf are the same. Despite being exactly the same, when consumed by the silk worm, silk is produced. When visited by the bee, honey is produced. When consumed by the goat, dung is produced and when consumed by the musk deer, musk is produced. Only the design of a creator who is eternal and all powerful could cause so many diverse things to be produced from one substance. Otherwise, logic would demand that the end product of all be the same as the substance which entered all was the same.”
(‘Aqaa’id-ul-Islaam page.42)