diff --git a/barber-women.py b/barber-women.py
new file mode 100644
index 0000000..7742768
--- /dev/null
+++ b/barber-women.py
@@ -0,0 +1,157 @@
+from z3 import DeclareSort
+from z3 import Datatype
+from z3 import Distinct
+from z3 import Const
+from z3 import Consts
+from z3 import Function
+from z3 import ForAll
+from z3 import Exists
+from z3 import Implies
+from z3 import And
+from z3 import Or
+from z3 import Xor
+from z3 import Not
+from z3 import BoolSort
+from z3 import IntSort
+from z3 import Solver
+
+from functools import reduce
+from typing import Any
+from typing import List
+
+axioms: List[Any] = []
+
+Sig = Datatype('Sig')
+Sig.declare("Person")
+Sig.declare("Man")
+Sig.declare("Woman")
+Sig.declare("Barber")
+Sig = Sig.create()
+
+Type = DeclareSort('Type')
+Instance = DeclareSort('Instance')
+subtype = Function('subtype', Type, Type, BoolSort())
+
+x, y, z = Consts('x, y, z', Type)
+inheritance_axioms = [
+    ForAll(x, subtype(x, x)),
+    ForAll([x, y, z], Implies(And(subtype(x, y), subtype(y, z)),
+                              subtype(x, z))),
+    ForAll([x, y], Implies(And(subtype(x, y), subtype(y, x)),
+                           x == y)),
+    ForAll([x, y, z], Implies(And(subtype(x, y), subtype(x, z)),
+                              Or(subtype(y, z), subtype(z, y)))),
+]
+
+a, b = Consts('a b', Instance)
+typeOf = Function('typeOf', Instance, Type, BoolSort())
+inClass = Function('inClass', Instance, Type, BoolSort())
+hasSig = Function('hasSig', Instance, Sig, BoolSort())
+s, o = Consts('s o', Sig)
+instance_axioms = [
+    ForAll([a, s, o], Implies(And(hasSig(a, s), hasSig(a, o)), s == o)),
+    ForAll([a], Exists([s], hasSig(a, s))),
+    ForAll([a], Exists([x], typeOf(a, x))),
+    ForAll([a, x, y], Implies(And(typeOf(a, x), typeOf(a, y)), x == y)),
+    ForAll([a, x], Implies(typeOf(a, x), inClass(a, x))),
+    ForAll([a, x, y], Implies(And(inClass(a, x), subtype(y, x)),
+                              inClass(a, y))),
+]
+
+axioms.extend(inheritance_axioms)
+axioms.extend(instance_axioms)
+
+
+# abstract sig Person {shaves: set Man}
+# sig Man, Woman extends Person{}
+# one sig Barber in Person {} // must be 'in' not 'extends':
+
+Man = Const("Man", Type)
+Woman = Const("Woman", Type)
+Person = Const("Person", Type)
+ax = [
+    subtype(Person, Man),
+    subtype(Person, Woman),
+
+    Not(Exists([a], hasSig(a, Sig.Person))),
+    Not(Exists([a], typeOf(a, Person))),
+    ForAll([a], Implies(hasSig(a, Sig.Man), typeOf(a, Man))),
+    ForAll([a], Implies(hasSig(a, Sig.Woman), typeOf(a, Woman))),
+    ForAll([a], Implies(hasSig(a, Sig.Barber), inClass(a, Person))),
+]
+axioms.extend(ax)
+
+
+shaves = Function('Person::shaves', Instance, Instance, BoolSort())
+ax = [
+    ForAll([a, b], Implies(shaves(a, b),
+                           And(inClass(a, Person), inClass(b, Man))))
+
+]
+axioms.extend(ax)
+
+
+ax = [
+    # lone constraint
+    Exists(a, hasSig(a, Sig.Barber)),
+    # one constraint
+    ForAll([a, b], Implies(And(hasSig(a, Sig.Barber), hasSig(b, Sig.Barber)),
+                           a == b)),
+]
+
+axioms.extend(ax)
+
+# fact {
+#   Barber.shaves = {m: Man | m not in m.shaves}
+# }
+
+ax = [
+    ForAll(a, Implies(
+        hasSig(a, Sig.Barber),
+        ForAll(b,
+               Implies(
+                   inClass(b, Man),
+                   And(
+                       shaves(a, b),
+                       Not(shaves(b, b))
+                   ))))),
+]
+axioms.extend(ax)
+
+ax = [
+    ForAll(a, Or(
+        hasSig(a, Sig.Man),
+        hasSig(a, Sig.Barber),
+        hasSig(a, Sig.Person),
+        hasSig(a, Sig.Woman),
+    ))
+]
+axioms.extend(ax)
+
+# run { }
+
+inst1 = Const('inst1', Instance)
+inst2 = Const('inst2', Instance)
+
+ax = [
+    hasSig(inst1, Sig.Man),
+    ForAll(a, Or(a == inst1, a == inst2)),
+    ForAll(x, Or(x == Man, x == Woman, x == Person)),
+]
+axioms.extend(ax)
+
+
+s = Solver()
+
+
+for i, c in enumerate(axioms):
+    s.assert_and_track(c, str(i) + c.__str__())
+
+s.assert_and_track(Distinct(inst1, inst2), "distinct")
+#s.assert_and_track(ForAll([a], And(a < 2, a >= 0)), "maxsize")
+
+
+print(s.check())
+m = s.model()
+g = Const("g", Sig)
+test = Const("test", Type)