I agree. This teacher has studied and taught for over thirty years so I'm guessing he thinks he does have evidence, but you're right, he'd have to demonstrate it.
That's a rather unwarranted guess! And even then there are different types of evidence. Your teacher's comment reminds me of Anatoly Fomenko, a very successful Russian mathematician who branched out into history. He postulates an Eurasian empire which fell apart in the 1400’s with each fragment taking on the history of that empire as its own national history and re-interpreting it as taking place in different times with different people and places. So, for example, English history from 500 to 1000 is the same as Byzantine history from 200 to 700, just reinterpreted. The Trojan wars were the same as the Crusades; Jesus was a Russian born in 1152, and was crucified in Istanbul. All of this is based on comprehensive statistical
evidence.
On the other hand, based on the little you've said, your teacher could simply be affirming that "there is nothing new under the sun", that the essence of all these processes and events have been seen before and after. An unbelieving corollary of that might be that if you wait long enough you will certainly find a situation that seems to fit with any prophecy.