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My recent ideas about sedimentary cycles in the distant past have been tempered by discussions with A. Fischer B. Berggren N. Christie-Blick D. Kent P. Olsen P. Lohmann L. Hinnov P. deMenocal F. Read J. Banner and B. Cecil. It was a push by T. Edgar that launched me down this track. Over the years discussions with M. Bender G. Denton J. Jouzel G. Bond R. Alley J. Severinghaus and J. Imbrie have molded my thinking about the events of the Late Quaternary. In this case it was ideas about multiple climate states expressed to me by H. Oeschger in 1984 that sparked my thinking. My research on the oceans has benefited from the wisdom of T. Stocker T. Takahashi S. Rahmstorf R. Toggweiler E. Maier-Reimer S. Manabe J. Marotzke J. McWilliams U. Mikolajewicz A. Gordon and P. Schlosser. It was the late H. Stommel who inspired me to a new level of thinking and action (that is the GEOSECS program). S. Peacock has worked with me on the problem of deep water formation in the Southern Ocean. J. Totton and P. Catanzaro transformed my hand scribbles into readable manuscript.