cognition and of being an object of cognition and will be the first and principal part of phenomenology as a whole. 

Phenomenology: this denotes a science, a system of scientific disciplines. But it also and above all denotes a method and an attitude of mind, the specifically philosophical attitude of mind, the specifically philosophical method. 

In contemporary philosophy, insofar as it claims to be a serious science, it has become almost a commonplace that there can be only one method for achieving cognition in all the sciences as well as in philosophy. This conviction accords wholly with the great philosophical traditions of the seventeenth century, which also thought that philosophy's salvation lay wholly in its taking as a model of method the exact sciences, and above all, mathematics and mathematical natural science. This putting philosophy methodologically on a par with the other sciences goes hand in hand with treating them alike with respect to subject matter. It is still the prevailing opinion that philosophy and, more specifically, ontology and the general theory of knowledge not only relate to all the other sciences, but also that they can be grounded upon the conclusions of those other sciences: / in the same way in which sciences are built upon one another, and the conclusions of one of them can serve as premises for the others. I am reminded of the favorite ploy of basing the theory of knowledge on the psychology of cognition and biology. In our day, reactions against these fatal prejudices are multiplying. And prejudices they are.

In the sphere of ordinary inquiry one science can readily build upon another, and the one can serve the other as a model of method even though to a limited extent determined by the nature of the areas of inquiry in question. But philosophy lies in a wholly new dimension. It needs an entirely new point of departure and an entirely new method distinguishing it in principle from any "natural" science. This is why the logical procedures that give the sciences of a natural sort unity have a unitary character in principle in spite of the special methods which change from one science to another: while the methodological procedures of philosophy have by contrast and in principle a new unity. This is also why pure philosophy, within the whole of the critique of cognition and the "critical" disciplines generally, must disregard, and must refrain from using, the intellectual achieve?ments of the sciences of a natural sort and of scientifically undisciplined natural wisdom and knowledge. 

To anticipate, this doctrine, the grounds for which will be given in more detail in the sequel, is recommended by the following considerations. 

In the sceptical mood which critical reflection about