a chicken-and-egg problem

a chicken and egg situation/problem

A situation in which it is unknown what happened, or what needs to happen, first. You need experience to get a job, but you need a job to get experience. It's a chicken and egg situation.

a chicken-and-egg problem

an unresolved question as to which of two things caused the other.
This expression comes from the traditional riddle: ‘which came first, the chicken or the egg?’
See also: problem
References in periodicals archive ?
(Troen and Boles wrestle with this dilemma partly by proposing intermediate ways to infuse existing schools with some of the characteristics of Millennium Schools.) Moreover, there is a chicken-and-egg problem. We need Millennium Schools to attract more good teachers, but plenty of good teachers are a prerequisite for having many successful Millennium Schools.