Testability is at the heart of virtually all philosophical conceptions of scientific theory. Verificationists, confirmationists, and falsificationists share the belief that scientific theories must be in some manner testable. The Kuhnian concept of a critical "anomaly" that undermines accepted standard concepts also implicitly invokes a notion of falsification—the anomaly stands out against a background of paradigmatic expectation, thus providing partial grounds for rejection of previously held views.¹ More recently, social constructionists have greatly challenged the determinative nature of empirical evidence, but recent constructionist accounts nevertheless allow an important role for experimental tests, even if placing the use and intepretation of those tests in a firmly social context.²