 A related issue has to do with whether all scientific explanations are causal and if not, what distinguishes causal from non-causal explanations. Hempel recognized both causal and non-causal forms of explanation but held that both were captured by the DN model –in his view, causal explanations are simply DN explanations that cite causal laws (which he regarded as a proper subset of all laws). Many but not all of the accounts discussed below in effect assume that many of the problems with the DN model can be traced to its commitment to an inadequate account of causation; thus that getting clearer about causal notions would lead to more adequate accounts of explanation. By contrast, a substantial amount of recent discussion of explanation has moved away from this focus on causation and instead explores the possibility of non-causal forms of explanation.[1] 