Μέμνησο νέος ὤν, ὡς γέρων ἔσῃ ποτέ → Iuvenis memento te fore aliquando senem → Bedenke jung schon, dass dereinst ein Greis du bist
See continuance.
that which comes next to: P. τὸ ἑξῆς (gen. or dat.).
the continuation of the argument: P. ὁ ἑξῆς λόγος.