Lately, I've been interested in logic, mainly to get answers to many questions I ask myself that I feel if left unanswered, I will never be satisfied with how I understand the way things work and are. One thing bothers me: I haven't found an author who makes a proper treatise of "where to start". I know nothing can be ever said or done if we constantly try to give definitions and meanings to things that refer to previously established definitions and meanings - one has to stop at the intuitive level. But the question is, where do we set this "intuitive level"? What words, aspects of our speech and logic should should we delegate to intuition, and which ones should we clearly define?