The acoustic version of this song can be found on youtube :
http://www.youtube.com/results?search_query=nature+is+the+law

Chords Used:

    D  Asus4   G  Cadd9
e|--2----0----3----3--
B|--3----3----3----3--
G|--2----2----0----0--
D|--0----0----0----2--
A|--x----0----2----3--
E|--x----x----3----x--

The Four chord are used throughout the song in the same order as the intro:-


INTRO:  D--Asus--G--D--Asus--G--D--Asus--G--Cadd9--G

D    Asus4       G
Old river and your
D        Asus4         G 
Restless wonder and your
D        Asus4       G     Cadd9   G
Graceful leisure rolling to the sea
D   Asus4      G   D     Asus4    G 
How many men have stood like I am
D      Asus4      G    Cadd9     G 
Gazing out and wishing for someone
D    Asus4       G 
Some are living and
D    Asus4       G 
Some are dead and
D    Asus4        G       Cadd9     G 
Some are hiding, waiting for the sun 

D             Asus4   G
Nature is the law, baby
D             Asus4    G 
Nature is the law, now baby now

D  Asus4  G   Cadd9  G

D             Asus4   G 
Nature is the law, baby
D            Asus4     G 
Nature is the law, now baby now 

D  Asus4  G   Cadd9   G