diff --git a/stix2/base.py b/stix2/base.py
index 4121570..cda1766 100644
--- a/stix2/base.py
+++ b/stix2/base.py
@@ -36,10 +36,6 @@ def get_required_properties(properties):
 class _STIXBase(collections.Mapping):
     """Base class for STIX object types"""
 
-    @classmethod
-    def _make_id(cls):
-        return cls._type + "--" + str(uuid.uuid4())
-
     # TODO: remove this
     def _handle_old_style_property(self, prop_name, prop_metadata, kwargs):
         cls = self.__class__
@@ -50,10 +46,6 @@ class _STIXBase(collections.Mapping):
                 default = prop_metadata['default']
                 if default == NOW:
                     kwargs[prop_name] = self.__now
-                else:
-                    kwargs[prop_name] = default(cls)
-            elif prop_metadata.get('fixed'):
-                kwargs[prop_name] = prop_metadata['fixed']
 
         if prop_metadata.get('validate'):
             if (prop_name in kwargs and
@@ -121,8 +113,6 @@ class _STIXBase(collections.Mapping):
 
     # Handle attribute access just like key access
     def __getattr__(self, name):
-        if name.startswith('_'):
-            return super(_STIXBase, self).__getattr__(name)
         return self.get(name)
 
     def __setattr__(self, name, value):
diff --git a/stix2/properties.py b/stix2/properties.py
index 08f7c31..78a3d2d 100644
--- a/stix2/properties.py
+++ b/stix2/properties.py
@@ -49,7 +49,7 @@ class Property(object):
             raise ValueError("must equal '{0}'.".format(self._fixed_value))
         return value
 
-    def __init__(self, required=False, fixed=None, clean=None, validate=None, default=None):
+    def __init__(self, required=False, fixed=None, clean=None, default=None):
         self.required = required
         if fixed:
             self._fixed_value = fixed
@@ -57,8 +57,6 @@ class Property(object):
             self.default = lambda: fixed
         if clean:
             self.clean = clean
-        if validate:
-            self.validate = validate
         if default:
             self.default = default
 
@@ -73,19 +71,6 @@ class Property(object):
         return value
 
 
-class TypeProperty(Property):
-
-    def __init__(self, type):
-        self.type = type
-
-    def validate(self, value):
-        if value != self.type:
-            raise ValueError("Invalid type value")
-
-    def default(self):
-        return self.type
-
-
 class List(Property):
 
     def __init__(self, contained):