One essay by this thinker states that "Formalized deductive disciplines" are, from the standpoint of the titular discipline, "meaningful sentences" or "certain inscriptions of a well defined form" and uses the concepts of "sentence" and "consequence" in order to create an "axiom system" by which the titular discipline can be defined. Another essay by this thinker has sections which explore "The Concept of the True Sentence" in" Everyday or Colloquial Language" as well as "Languages of Infinite order" in order to present "the definition of truth
One essay by this thinker states that "Formalized deductive disciplines" are, from the standpoint of the titular discipline, "meaningful sentences" or "certain inscriptions of a well defined form" and uses the concepts of "sentence" and "consequence" in order to create an "axiom system" by which the titular discipline can be defined. Another essay by this thinker has sections which explore "The Concept of the True Sentence" in" Everyday or Colloquial Language" as well as "Languages of Infinite order" in order to present "the definition of truth." Those essays, "On Some Fundamental Concepts of Metamathematics," and "The Concept of Truth in Formalized Language" are all collected in this thinker's Logic, Semantics, Mathematics. For 10 points name this thinker, author of a famous Introduction to Logic. 
One essay by this thinker states that "Formalized deductive disciplines" are, from the standpoint of the titular discipline, "meaningful sentences" or "certain inscriptions of a well defined form" and uses the concepts of "sentence" and "consequence" in order to create an "axiom system" by which the titular discipline can be defined.
Alfred Tarski