Why don't ice cubes spontaneously form in a cup of water? Someone was explaining to me that for ice cubes to spontaneously form, the water molecules would have to go to a more ordered state. I know about the spontaneous symmetry breaking that occurs when water is at 0'C, but I was wondering if it's possible for the rest of the universe's entropy to increase more than the decreased entropy caused by the ice cubes forming. That way, the Second Law of Thermodynamics is not violated, and it still allows the ice cubes to form. Is this a question of chance then, that we'd have to wait a long enough cosmological time span for the entropy in all other areas of the universe to suddenly increase to such an extent as to make up for the ice cubes forming? Thanks for answering.