discussions about forms of life

“[I]t can be pointed out that discussions about forms of life and world pictures do in fact take place. […] Perhaps even more important is the following: it is necessary to distinguish between the observation that neither the process of justification nor that of criticism can proceed without presuppositions or assumptions and the thesis that what is presupposed or assumed is in the last analysis not open to discussion (that is, is open neither to justification nor to criticism). The latter does not follow from the former. The view that all presuppositions or assumptions may be questioned is of course open to the objection that in discussing one lot of assumptions further assumptions have to be made, so that it is impossible to conceive of a situation which is well-founded in all its aspects. However, the thesis that every assumption is open to discussion does not maintain that everything can be justified simultaneously. It says only that there is no assertion such that the possibility of some argument being advanced for or against it is excluded a priori.” (Robert Alexy. A Theory of Legal Argumentation. pp. 52-53)