The present thesis is an analytical study of the vipassanananana, and solasanana. The presentation begins with by exploring the background of these terms, which are not found in the discourses. The main purpose for studying the term solasanana is to trace it back to discover what was said in the discourses and their development. What content is provided by the discourses and the post-canonical literature? The observation proceeds by fist selecting key Pali terms that involve the theory of knowledge, and then by isolating their meanings in the process of knowing.
     The middle part of the thesis deals with the development of the sixteen stages as an approach to the understanding of the Buddhist view of reality. The characteristic of intrinsic-nature and the three universal characteristics of impermanent, suffering, and not-self are described. The two levels of reality, conventional and ultimate, are discussed. The aim of studying is also distinguishable between the knowable and knowledge. Knowledge can be demonstrated by understanding. The knowable can be demonstrated by the past, future, and presently arisen, by the in-oneself and external, by the profitable, or unprofitable; in brief by the six objects (of the six bases in oneself).
     The last part of the thesis is concerned with the causes and conditions of the arising and of the weakening of insight knowledge. These causes and conditions are divided into two main parts, internal and external. These causes and conditions are isolated from several discourses, in most of which they appear as part of a sequence leading to the arising of knowledge of things as they really are. These sequences designate conditions for phenomena that, in turn, support the arising of support the arising of subsequent conditions. The observation of the causes and conditions of the arising or weakening of insight knowledge demonstrates the Law of Regularity, which is part of the very nature of the existence. Nothing arises by itself. Conclusions are drawn and suggestion for further research are made.