diff --git a/lib/arm/arm_machine.rb b/lib/arm/arm_machine.rb
index 9c7bfed0..bab40ca6 100644
--- a/lib/arm/arm_machine.rb
+++ b/lib/arm/arm_machine.rb
@@ -15,7 +15,7 @@ module Arm
   class ArmMachine
 
     # conditions specify all the possibilities for branches. Branches are b + condition
-    # Example:  beq means brach if equal.
+    # Example:  beq means branch if equal.
     # :al means always, so bal is an unconditional branch (but b() also works)
     CONDITIONS = [:al ,:eq ,:ne ,:lt ,:le ,:ge,:gt ,:cs ,:mi ,:hi ,:cc ,:pl,:ls ,:vc ,:vs]
 
diff --git a/lib/mom/instruction/basic_values.rb b/lib/mom/instruction/basic_values.rb
index 3b143896..69316c33 100644
--- a/lib/mom/instruction/basic_values.rb
+++ b/lib/mom/instruction/basic_values.rb
@@ -25,17 +25,17 @@ module Mom
   end
   class TrueConstant < Constant
     def ct_type
-      Parfait.object_space.get_class_by_name(:True).instance_type
+      Parfait.object_space.get_class_by_name(:TrueClass).instance_type
     end
   end
   class FalseConstant < Constant
     def ct_type
-      Parfait.object_space.get_class_by_name(:False).instance_type
+      Parfait.object_space.get_class_by_name(:FalseClass).instance_type
     end
   end
   class NilConstant < Constant
     def ct_type
-      Parfait.object_space.get_class_by_name(:Nil).instance_type
+      Parfait.object_space.get_class_by_name(:NilClass).instance_type
     end
   end
   class StringConstant < Constant
diff --git a/lib/parfait/integer.rb b/lib/parfait/integer.rb
index 868125df..d32aa43f 100644
--- a/lib/parfait/integer.rb
+++ b/lib/parfait/integer.rb
@@ -1,6 +1,6 @@
 
 # Integer class for representing maths on Integers
-# Integers are Objects, spcifically DataObjects
+# Integers are Objects, specifically DataObjects
 # - they have fixed value
 # - they are immutable
 # (both by implementation, not design.
@@ -21,4 +21,12 @@ module Parfait
     # :quo, :to_c, :real, :imaginary, :imag, :abs2, :arg, :angle, :phase, :rectangular, :rect, :polar, :conjugate, :conj,
     # :>, :>=, :<, :<=, :between?
   end
+
+  # adding other base classes in here for now:
+  class FalseClass
+  end
+  class TrusClass
+  end
+  class NilClass
+  end
 end
diff --git a/lib/risc/boot.rb b/lib/risc/boot.rb
index 138efd0a..3d7e9d88 100644
--- a/lib/risc/boot.rb
+++ b/lib/risc/boot.rb
@@ -129,10 +129,15 @@ module Risc
                         :return_address => :Integer, :return_value => :Integer,
                         :caller => :Message , :name => :Word , :arguments => :NamedList },
           :Integer => {},
+          :TrueClass => {},
+          :FalseClass => {},
+          :NilClass => {},
           :Object => {},
           :Kernel => {}, #fix, kernel is a class, but should be a module
           :BinaryCode => {:char_length => :Integer} ,
-          :Space => {:classes => :Dictionary , :types => :Dictionary , :first_message => :Message},
+          :Space => {:classes => :Dictionary , :types => :Dictionary ,
+                     :first_message => :Message , single_true: :TrueClass,
+                     single_false: :FalseClass , single_nil: :NilClass},
           :NamedList => {},
           :Type => {:names => :List , :types => :List  ,
                     :object_class => :Class, :methods => :List } ,