 A common initial objection to HOT theory (or even HOP) is that they lead to an infinite regress.  It might seem that an infinite regress results because a conscious mental state (M) must be accompanied by a HOT, which, in turn must be accompanied by another HOT and so on. However, the standard and widely accepted reply or explanation is that when M is conscious, the HOT is not itself conscious (Rosenthal 1986, 2005).  M is a first-order world-directed conscious state, such as a desire or perception, accompanied by an unconscious HOT. But when the HOT is itself conscious, there is a yet another higher-order (or third-order) thought directed at the conscious HOT. This would be a case of introspection according to HOT theory such that one’s attention is directed inward at M (such as introspecting my desire). When this crucial distinction is overlooked, it can lead to some misguided objections such as supposing that, according to HOT theory, having any conscious state (even for animals and infants) requires the ability to introspect.