Towards the end of his enquiry into the nature of perception, Heidegger says a further understanding needs to be brought into focus, one which relates to us as the beings that perceive.
As we have seen perception is characterised as a duality, split between what strikes our senses, which is immediately and naturally given; and our understanding of what was previously called the excess, which is only achieved with effort over time. Similarly we are ourselves split, between our bodily relationship to that which we receive naturally, i.e. from nature, which conditions us; and our struggle to understand being over the course of the history of our being.
Heidegger characterises our being as Dasein, as “being-in-the-world,” this means we are not detached observers, but, from the moment of our birth, subject to the power of nature, experienced as “day and night, land and sea, generation, growth and decline, winter and summer, sky and earth.” We experience nature as something beyond our control, indeed as something which tunes us in our essence, i.e. in our striving for being. We experience this attunedness as “joy and cheerfulness, anxiety and misery.” Yet these moods do not control us, instead it is our Dasein as striving that “seizes hold” of our bodily being in its powerlessness in the face of nature, and directs it in its striving relationship with being, the ground of our essence. (170)
From this Heidegger says that our understanding of being as striving is not achieved through nature, but by the effort and patience of paideia (learning), a commitment of our authentic selves to striving itself, which is seldom achieved. “This is the reason we find it so difficult to grasp what this word (striving) refers to.” (171)