In three books, which belong to the last period of his life, Husserl laid down the program for a phenomenological theory of logic (understood in a very broad sense) and the sciences, especially physics, and took decisive steps towards its implementation¹. According to this program, the disciplines in question have to be referred, and their phenomenological origin or genesis of sense (Sinnesgenese) has to be traced back to perceptual consciousness.² The guiding idea is that perceptual consciousness contains the germs or roots of whatever entities are the subject matter of study in the disciplines in question, and that those entities are brought to full development and given their definitive shape by means of specific mental operations.