The Song of Los, probably written in 1794-5, is one of Blake's most startling indictments of tyranny. Although the first of its two parts, subtitled “Africa”, does have some more or less precise historical and geographical referent, it also gives Blake the opportunity to speak of some of his abiding general concerns:
These were the churches, hospitals, castles, palaces,
Like nets and gins and traps to catch the joys of Eternity,
And all the rest a desert;
Till like a dream Eternity was obliterated and erased.
Human institutions, no matter what their ostensible object, are all seen from this perspective as forces for the reduction and constraint of experience and as ways o…