Dave is big. Dave is cold. Dave is not young. If Dave is big and Dave is red then Dave is not green. All green, smart things are young. If something is smart and quiet then it is green. Big things are smart. If something is quiet and not big then it is not smart. If Dave is smart then Dave is red. If something is smart and not green then it is red. If something is not green then it is not young.
Dave is not smart.