The particular world that human beings inhabit is called physical nature, whose laws are known as the laws of science. How can it be _one_ world in which so many millions of different human beings live? Because these millions of human beings are under the same fundamental rational laws, and they construct the world in a common fashion. The laws of nature are, after all, the laws of our own minds. They are the laws of reason. The laws of nature are not the laws of absolute reality, but the laws of the human interpretation of reality. All the linkage of facts, all the law and order of our universe, all the combination of the variety of objects of knowledge――in a word, the entire body of science or the world of physical nature is a human mental synthesis. Does independent absolute reality exist? Yes; but it exists behind the scenes for us as for the angels. Mental synthesis is constitutive of the world in which we are actually engaged――mental synthesis is shot through and through all our experiences. Mental synthesis is the framework of the universe, and therefore Kant says, “The world is my representation.” =The Judgments Indispensable to Human Knowledge.= It will be seen from the above discussion that Kant does not believe that an idea or a sensation taken by itself constitutes knowledge. Knowledge consists of sensations framed together in a synthesis. That is, ideas must be taken together with other ideas. This is called in grammar a proposition, having a subject and a predicate. In logic it is called a judgment. The only way a human being can express knowledge is in the form of judgments, but all judgments of human beings are not necessarily knowledge.