Since its publication in 1921, Wittgenstein's Tractatus Logico-Philosophicus has attracted a broad variety of interpretations. The work has been viewed as a revolution in the metaphysics of logic, with Wittgenstein inventing the truth-tables and ushering in modern logic and even modal logic. It has been viewed as the holy text of the antimetaphysical doctrines of logical empiricism – a work attempting to establish a foundational observation language grounding empirical (scientific) discourse in an effort to show that all philosophical or metaphysical propositions are pseudo-propositions. Wittgenstein's attraction to the tragic lives of Schopenhauer, Weininger, and Kierkegaard has been a resource for irrationalist interpretations as well. Rejecting both logic and metaphysics as the focus of the Tractatus, they herald its entries on solipsism, value, religion, and mysticism as central to its message. Therapeutic interpretations attempt an even more radical break than do irrationalist interpretations. The therapeutic reading denies that there is any positive philosophical theory in the work. On this reading, the Tractatus is against philosophical theory and offers a treatment for the condition of thinking that there are riddles that must be solved by a philosophical theory. Thus, we find diametric opposition among even the most prominent philosophical interpretations of the Tractatus. We find those that take its central focus to be in epistemology, ontology, logic, semantics, ethics, religion, mysticism, or all of these together. We find interpretations of the text as realist, physicalist, phenomenalist, solipsist, idealist, existentialist, irrational, and therapeutic.