Did Plato know anything that noone knows now?

I'm sure he knew volumes that no one knows today, from the exact date of his own birth to the day-to-day minutiae of his life. Did he possess useful scientific knowledge that we no longer have today? I'm almost as sure that the answer to that is no.

He understood human behaviour.

If he did, we wouldn't know.

if no one knew it he couldnt either then it wouldnt be something no one knew 😉