The dynamics of law and economics in the cannon of American legal thought was initially characterized by a denial of the independence of contract law, tailored by judicial decisions and the realist revolution. This paper shows that this denial begets the rebirth of contract law based on policy doctrines that asked for the turn to economics, by giving a new linguistic framework and foundation to contracts. After such process, an inconspicuous doctrine of contract law was built by the Critical Legal Studies (CLS) doctrine. Its effect was not constructive but deconstructive, but purposeless and proposeless. After the failure of CLS, law and economics consolidated as the actual base of US contract law.