A real X is defined to be relatively c.e. if there is a real Y such that X is c.e.(Y) and $${X \not\leq_T Y}$$ . A real X is relatively simple and above if there is a real Y < T X such that X is c.e.(Y) and there is no infinite set $${Z \subseteq \overline{X}}$$ such that Z is c.e.(Y). We prove that every nonempty $${\Pi^0_1}$$ class contains a member which is not relatively c.e. and that every 1-generic real is relatively simple and above.
['Bernard A. Anderson']
Relatively computably enumerable reals