To the Editor.
—In their article, Dr Gold and colleagues1 commend a recent Supreme Court decision that interpreted a Federal Rule of Evidence addressing the courtroom admissibility of scientific evidence. The authors portray the Court as striking an effective compromise between those seeking stringent standards of admissibility in order to prevent scientifically unproven testimony from being presented at trial and those arguing for looser standards in order that potentially valuable testimony not be excluded.One cannot fault the Court for its reasonable interpretation of a Federal Rule of Evidence that has been legislatively enacted. However, the rule itself as chronicled by Huber2 appears to be part of a general trend replacing established concepts of causation with chains of causal elements extending through time and place. Courts can use discretion in placing the costs of injuries on various elements along the causal chain, at times supported by dubious economic