Again, continuing with my (educated) guesswork... R and S, in the last two lines, seem to indicate the trueness or fallacy of a statement. R(statement)R is a true, well-formed statement. S(statement)S is a false statement. For usage, see the last two lines, where (using Q notation, indicating that we should expect this in the future), "(2=1+1) is true!", "(3=1+1) is false!" That's all I've got right now, but I'm working...