37 Preface وَآيَةٌ لَهُمُ اللَّيلُ نَسلَخُ مِنهُ النَّهارَ فَإِذا هُم مُظلِمونَYusuf AliAnd a Sign for them is the Night: We withdraw1 therefrom the Day, and behold they are plunged in darkness;Withdrawing the Day from the Night: is a striking phrase and very apt. The Day or the Light is the positive thing. The Night or Darkness is merely negative. We cannot withdraw the negative. But if we withdraw the real thing, the positive, which filled the void, nothing is left but the void. The whole of this section deals with Signs and Symbols-things in the physical world around us, from which we can learn the deepest spiritual truths if we earnestly apply ourselves to them.