CONTENTS § 1. Introduction ............................................................................................................ 5 § 2. The ε-calculus for {є}............................................................................................ 6 § 3. Reflection principles in e-set theories.............................................................. 6 § 4. [E]-elementary chains.......................................................................................... 11 § 5. Forcing and reflection .......................................................................................... 14 § 6. $\hat{ε}$-deductions and the main result........................................................ 23 § 7. Appendix: on Zermelo's set theory with the axiom of choice........................ 24 References ................................................................................................................... 27