ABSTRACT
Sir William Blackstone catalogued the four unities of the joint tenancy, usually summarized as time, title, interest, and possession. The ancient estate in coparcenary occupied Blackstone next. The fractured foundation on which the law of tenancy by the entirety was subsequently built is revealed in Blackstone's one-sentence afterthought. The forces that carried the tenancy by the entirety into the modern world included more than simple inertia, although that undoubtedly played a part. Although verbally the tenancy by the entirety was equated with the joint tenancy, subject to the significant exception of the indefeasible right of survivorship, it remained a concurrent estate with strikingly different qualities. The creative juices of the common law courts had now seemingly dried up, and legislative solutions were required. The tenancy by the entirety since Blackstone has been an awkward compromise, renegotiated in each generation, and only belatedly catching up with social reality.
