I thought I was the only one who pondered that! I think we'd have even more fun times in 1st century CE Alexandria.

They'd burn you at the stake.

This comment got me thinking: if that were to happen unexpectedly, how would you

1) determine when and where you were, and

2) convince the locals who probably don't speak your language or look like you not to kill or imprison you?

3) Live for more than a few days, with bacterial fauna of that time being so different, your immune system, completely unpolished for those type of bugs, would probably hold out for only a very short time.

Your immune system carries memories of those days.

With antibiotics prevalent that memory may be fuzzy

Wouldn't a book on microbiology be much more useful to humanity?