This paper explores how the self-constitution of the social order is affected by a property of human desire that is seldom taken seriously in the social sciences, namely the fact that desire is essentially triangular. It brings into play a subject, an object, and a mediator or third party whom the subject imitates. It is suggested that the difficult issue of the embodiment of social cognition finds its solution in the role played by the third party. It is shown that Friedrich Hayek and John Maynard Keynes were familiar with this pattern. The paper focuses on the role played by imitation in Hayek's conception of the social order as spontaneous or self-organized. Many apparent contradictions in Hayek's social philosophy are explained (away) when one realizes that Hayek remains oblivious to the ambivalence of imitation. Imitation is efficient if the correct information is present somewhere and recognized as such, but otherwise it becomes a source of illusions and waste. The problem is that it is impossible from inside the system to know in which of the two cases one finds oneself. To overcome this undecidability, it is necessary to resort to an exteriority. Generalized imitation has the power to create worlds that are perfectly disconnected from reality: at once orderly, stable, and totally illusory. The notion of collective or social self-deception is illustrated with the case of gift giving. The conclusion of the paper is devoted to a critique of the notion of truth in American pragmatism in that it ignores that possibility altogether.