The idea of phenomenology

The author here engages in the 'philosophical history of philosophical ideas'. This distinguishes him from those who do 'philosophical history' of ideas from outside the domain of philosophy proper, and on the other hand from those who do 'historical history' of philosophical ideas. By philosophical history in general, I mean an account of the 'conceptual lineage' of ideas or systems of ideas, a discerning of the relations between ideas or systems of ideas, a discerning of the relations between ideas with respect to their content and their logical order of precedence, apart from the historical sequence in which they are introduced and developed. The author's ambition is to carry out such 'historical' inquiries in the form of a structural analysis of philosophy, which he regards as a rigorous philosophical discipline -- that is, as a science. -- Translator's Introduction.