Natural rubber Natural rubber Natural rubber, also called India rubber or caoutchouc, as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds, plus water. Malaysia and Indonesia are two of the leading rubber producers. Forms of polyisoprene that are used as natural rubbers are classified as elastomers. Currently, rubber is harvested mainly in the form of the latex from the rubber tree or others. The latex is a sticky, milky colloid drawn off by making incisions in the bark and collecting the fluid in vessels in a process called "tapping". The latex then is
Substance theory which "we can understand nothing else than an entity which "is" in such a way that it need no other entity in order to "be"." Therefore, only God is a substance as "Ens perfectissimus" (most perfect being). Heidegger showed the inextricable relationship between the concept of substance and of subject, which explains why, instead of talking about "man" or "humankind", he speaks about the "Dasein", which is not a simple subject, nor a substance. Alfred North Whitehead has argued that the concept of substance has only a limited applicability in everyday life and that metaphysics should rely upon the concept