This paper was the prologue to the first book published by Gabriel Barceló on
the Theory of Dynamic Interactions, entitled: The Flight of the Boomerang.
However, this text, is fully current, as well as the book itself. The book described
mainly the initial historical analysis made by Dr. Barceló on the rotational
dynamics. For Professor Garcia Moliner, the book contains an extremely
positive message. It shows us that scientific research consists of constantly
questioning hitherto accepted theories and seeing if they can always be
applied to new situations