Department of Cognitive Science and Psychology, New Bulgarian University, Sofia, Bulgaria.
J Eval Clin Pract. 2013 Jun;19(3):524-7. doi: 10.1111/jep.12051.
In 1973, P. Meehl drew attention to the fact that some clinicians tend to interpret the otherwise clear symptomatic behaviour of their patients as 'normal' if they are given a plausible causal story of patients' behaviours. He claimed that this way of thinking is, in fact, fallacious and gave the alleged fallacy the 'catchy' name 'understanding it makes it normal'. Thirty years later, the cognitive psychologists W.K. Ahn, L. Novick and N. Kim questioned the fallacy status of 'understanding it makes it normal' by arguing that this way of reasoning is not only quite common among clinicians but that it is in fact rational. The controversy over whether 'understanding it makes it normal' is a reasoning fallacy or not is still unresolved and this is evident from the recent discussion about the proposed removal of the 'normal grief' exclusion criterion for Major Depressive Disorder from DSM-5. This paper proposes an analysis of what stands behind the two opposing claims about 'understanding it makes it normal'. The analysis builds on the distinction between validity and utility of psychiatric diagnoses and reaches the following conclusions: (1) the fallacy claim is consistent with the assumption that the psychiatric diagnoses are valid descriptions of real mental disorders; (2) the non-fallacy claim is consistent with the opposite assumption that current psychiatric diagnoses are not valid but only useful descriptions and their utility varies across different contexts; (3) if we agree that there is not enough evidence for the validity of the diagnostic categories embedded in DSM-4 and ICD-10, we should also agree that the behaviour of those mental health professionals who change their diagnoses under the influence of the causal context is rational; (4) nevertheless, the 'understanding it makes it normal' reasoning strategy should be considered a bias insofar as it takes into account only part of the causal context: the causes of the symptoms but not what they themselves might cause. The neglect of the latter might have dramatic negative consequences in clinical practice. In addition, some recent studies suggest that this bias probably has cultural roots.
1973 年，P·米尔（P. Meehl）提请人们注意这样一个事实，即一些临床医生如果能为患者的行为找到一个看似合理的因果解释，他们往往会将患者原本明显的症状表现解释为“正常”。他声称，这种思维方式实际上是错误的，并给这种所谓的谬论起了一个“生动”的名字——“理解它就使其正常”。30 年后，认知心理学家 W.K.安（W.K. Ahn）、L.诺维克（L. Novick）和 N.金（N. Kim）质疑“理解它就使其正常”是否属于谬误，他们认为这种推理方式不仅在临床医生中相当普遍，而且实际上是合理的。关于“理解它就使其正常”是否属于推理谬误的争议仍未解决，这从最近关于从 DSM-5 中删除“正常悲伤”这一排除标准的讨论中可见一斑。本文提出了对“理解它就使其正常”这两种对立观点背后原因的分析。该分析建立在精神科诊断的有效性和实用性之间的区别的基础上，并得出以下结论：（1）谬误观点与这样一种假设一致，即精神科诊断是对真实精神障碍的有效描述；（2）非谬误观点与相反的假设一致，即目前的精神科诊断不是有效的，而只是有用的描述，其有效性在不同的情况下有所不同；（3）如果我们同意 DSM-4 和 ICD-10 中包含的诊断类别没有足够的证据证明其有效性，我们也应该同意那些在因果背景影响下改变诊断的心理健康专业人员的行为是合理的；（4）然而，“理解它就使其正常”的推理策略应该被视为一种偏见，因为它只考虑了因果背景的一部分：症状的原因，但没有考虑到它们本身可能导致的原因。忽视后者可能会对临床实践产生戏剧性的负面影响。此外，一些最近的研究表明，这种偏见可能具有文化根源。
