Lem's Opinion
From today's perspective Eden is neutral in my eyes.  It is so-so.  From the point of view of literature it is a rather unsuccessful book;  its characters tend to be schematic and the pictured universe is a bit "flat" and one-dimensional.  This literature of the "second sort" is quite good in comparison with average science fiction - but one cannot line up a man of regular height with hunchbacks and claim that he is an Apollo.