Freud argues that the laws of classical logic do not hold true with regard to the unconscious. The aim of this paper is to provide an alternative logic that is consistent with Freud’s conception of the unconscious. This aim is achieved in two steps. First, I argue that most Freudian features of the unconscious are consequences of the fact that unconscious thoughts in the Freudian sense are negationless. Then I suggest a formal logical system that lacks the negation symbol, and is known as negationless-logic, with which to formulate the logic of the unconscious. I demonstrate that this suggestion provides a better understanding of various psychological phenomena, such as projection, reaction-formation, delusion and the misconstrual of the empty set in childhood. Finally, I argue that negationless-logic provides solutions to certain shortcomings in Matte-Blanco’s formulation of the logic of the unconscious.