'In the beginning,' my dear, "there was that only which is (τὸ ὄν), one only, without a second. Others say, in the beginning there was that only which is not (τὸ μὴ ὄν), one only, without a second; and from that which is not, that which is was born.

In plain words: The father begins: in the beginning there was only Being, one thing with nothing else beside it. He notes that some people say there was only nothing at first, and that being came out of nothing.