What man is he that desireth life, and loveth many days, that he may see good?
What man ... desireth life ... see good? Who is there that does not desire "life" in its fullest enjoyment? The Psalmist proceeds to describe the sure and only means for attaining it. The word "good" in the second clause, explains what is meant by the parallel "life" in the first clause. "Days" of 'seeing good' are life in its highest sense.
[nun (n)]