Organic chemistry no longer deserves the name it was given by the founders of chemistry. There is now abundant evidence that many so-called organic molecules can arise without the help of living organisms (including chemists) and that they do so on a very large scale throughout the cosmos (see Chapter 5). It seems likely that such abiotically formed compounds provided the first building blocks of life. Little is known, however, of the manner in which these compounds interacted further to generate increasingly complex molecules and molecular assemblages, up to the first living cells. To date, in spite of much experimental and theoretical work, a striking discontinuity still separates the most successful attempts at reproducing biogenic processes in the laboratory from the manner in which these processes take place in living organisms. Yet, an uninterrupted sequence of events must link abiotic chemistry historically to biochemistry.

Many suggestions have been made concerning the nature of this link. The most radical suggestion, inspired by the genetic-takeover concept of Cairns- Smith (1982), postulates that the early chemistry was totally unrelated to biochemistry and served only as a temporary framework, later to be dismantled without leaving traces, for the development of the new chemistry. At the other end of the spectrum, the proposal made in this chapter rests on the premise that abiotic chemistry merged into present-day biochemistry already at a very early stage. This contention is supported by the perceived need for congruence between the two chemistries (de Duve 1991, 1993, 1995).