EXPERIMENTAL APPROACHES TO THE ORIGIN OF LIFE PROBLEM By HOWARD H. PATTEE, Stanford, California CONTENTS I. Introduction 381 II. Abiogenic Syntheses in Simulated Primeval Environments 388 A. Review of Experiments 388 B. Discussion of Abiogenic Synthesis Experiments 389 III. Studies of Organized Structure 391 IV. The Search for Extraterrestrial Information 393 A. Meteorites and Planetary Landings 393 B. Discussion of Extraterrestrial Experiments 394 V. The Approach from Molecular Biology 395 A. Current Molecular Biological Theories 396 B. Discussion of Biological Approaches to the Origin of Life 397 VI. Abiological Approaches 399 A. Future of Abiogenic Syntheses 399 B. Contributions of Polymer Chemistry 401 VII. Theories of Macromolecular Evolution 405 A. Order from Disorder : 406 B. Order in Automata 407 C. Order Acquired by Learning 408 VIII. Conclusion 410 References 411 I. Introduction No question has aroused the curiosity of man for as long a time and provoked answers from so many disciplines as the primeval source of the persistent, localized, chemical reactions which we now recognize as living organisms. No doubt the question will continue to generate answers from many points of view for a long time to come. As a problem of experimental science i t has stimulated only sporadic interest in the past, but for good reasons a general renewal of interest has grown in the last decade. First of all there are now many dem- onstrations that reasonable, primitive earth-like environments can produce most classes of molecules which are essential for present living organisms. Second, the immanent possibility of landing life-