 This limits the expressive possibilities of first order logic. For example, let us suppose that we wish to amend our previous assertion about boys and girls as follows: every boy loves some girl that loves some other boy, and this second boy can be chosen independently on the first one. What this means, intuitively speaking, is simple enough: for every boy \(b\) we can find a girl \(g\) such that \(b\) loves \(g\), and for every such girl we can find a boy \(b'\) such that \(g\) loves \(b'\) and \(b \not = b'\), and furthermore we can find the identity of the second boy \(b'\) without knowing that of \(b\), on the basis of the identity of the girl \(g\) alone. This can still be the true in some scenarios, such as for example if two boys \(b_1\) and \(b_2\) love respectively two girls \(g_1\) and \(g_2\), who however love only \(b_2\) and \(b_1\) respectively. However, it is easily seen that it is not equivalent to our previous statement: for example, if our universe consists (as in (b) above) of two boys \(b\) and \(b'\) and a girl \(g\), and \(b\) and \(b'\) both love \(g\) who loves both of them, then our previous assertion is true but the current one is false.