Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-08-09T16:53:24Z No. of bitstreams: 1 IracemaFonsecaSiqueiradeAbreuDissertacao2016.pdf: 3500985 bytes, checksum: 19c297158844ecc0406ab0bbfb43ae8f (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-08-09T16:53:38Z (GMT) No. of bitstreams: 1 IracemaFonsecaSiqueiradeAbreuDissertacao2016.pdf: 3500985 bytes, checksum: 19c297158844ecc0406ab0bbfb43ae8f (MD5) / Made available in DSpace on 2017-08-09T16:53:38Z (GMT). No. of bitstreams: 1 IracemaFonsecaSiqueiradeAbreuDissertacao2016.pdf: 3500985 bytes, checksum: 19c297158844ecc0406ab0bbfb43ae8f (MD5) Previous issue date: 2017-02-23 / The present dissertation has the scope to present the institute of the single tax and to analyze it in the light of the principles of optimal taxation. The single taxation model has stood out due to its apparent simplicity and economic efficiency, being considered as a solution to the current complex and costly tax structures. In this way, the feasibility of the single tax is questioned in the current legal systems. Through an instrumental bibliographical procedure, the deduction was used to answer such problematic. For that, a priori, the history of the single tax, from the first records in France and the studies of Physiocracy, to the current Brazilian debate on the single federal tax on financial transactions was reported. In the second moment, the proposal was evaluated under the prism of the main theories of the optimal taxation of Smith, Musgrave, Neumark and Stiglitz. Finally, the last chapter developed the contemporary debate on the single tax, explaining its advantages and disadvantages, and then concluding on its viability or not. / A presente Disserta????o tem o escopo de apresentar o instituto do imposto ??nico e analis??-lo ?? luz dos princ??pios da tributa????o ??tima. O modelo de tributa????o ??nica tem se destacado devido ?? sua aparente simplicidade e efici??ncia econ??mica, sendo considerado como solu????o para as atuais estruturas tribut??rias complexas e onerosas. Dessa forma, questiona-se a praticabilidade do imposto ??nico nos ordenamentos jur??dicos atuais. Por meio de um procedimento instrumental bibliogr??fico, recorreu-se a dedu????o para responder tal problem??tica. Para isso, a priori, relatou-se o hist??rico do imposto ??nico, desde os primeiros registros na Fran??a e os estudos da Fisiocracia, at?? o debate atual brasileiro do imposto ??nico federal sobre movimenta????es financeiras. No segundo momento, a proposta foi avaliada sob o prisma das principais teorias da tributa????o ??tima de Smith, Musgrave, Neumark e Stiglitz. Por fim, o ??ltimo cap??tulo desenvolveu o debate contempor??neo acerca do imposto ??nico, explicitando suas vantagens e desvantagens, para, ent??o, concluir sobre sua viabilidade ou n??o.