This is a list of important landmarks in the history of systematic philosophical inquiry and scientific analysis of phenomena. The list seeks to highlight important stages in the development of thoughts and analysis towards conceptualizing and understanding phenomena. This list seeks to include all major landmarks in systematic analysis of phenomena across disciplines that seeks to implement formal methods and systematic formal analysis of phenomena. Thus it seeks to list major landmarks across all scientific philosophy and methodological sciences including physical sciences, , formal disciplines or pure sciences, behavioural sciences, social sciences, biological sciences, life sciences and other related disciplines.