[R] expression over-plotted

[Brad Eck]

   When I try to add the following annotation to a plot the entries are plotted
   one on top of the other.  I'm trying to get something that looks like " eta
   =  0.2  "  where the Greek letter is used on the plot.  I realize that
   expression( eta == 0.2) is one solution, but ultimately I'd like to use this
   in a legend that uses a loop to fill the entries so I don't want the 0.2
   entered manually.
   val <- 0.2
   plot( c(0,1), c(0,1) )
   text(  0.5, 0.5, c( expression( eta ), paste( ' = ', val ) ) )
   Thanks,
   Brad