diff --git a/src/FPGroups.jl b/src/FPGroups.jl
index 214ba7d..4f5a8dd 100644
--- a/src/FPGroups.jl
+++ b/src/FPGroups.jl
@@ -82,8 +82,6 @@ end
 
 hash(s::FPSymbol, h::UInt) = hash(s.str, hash(s.pow, hash(FPSymbol, h)))
 
-isone(s::FPSymbol) = s.pow == 0
-
 change_pow(s::FPSymbol, n::Int) = FPSymbol(s.str, n)
 
 length(s::FPSymbol) = abs(s.pow)
diff --git a/src/Groups.jl b/src/Groups.jl
index 4eea8f4..5c53105 100644
--- a/src/Groups.jl
+++ b/src/Groups.jl
@@ -86,6 +86,8 @@ function deepcopy_internal{T<:GSymbol}(W::GWord{T}, dict::ObjectIdDict)
     return G(GWord{T}(deepcopy(W.symbols)))
 end
 
+isone{T<:GSymbol}(s::T) = s.pow == 0
+
 length(W::GWord) = sum([length(s) for s in W.symbols])
 
 function free_reduce!(W::GWord)