Jesus did not rise from the dead -- My debate opening statement.

[GUBU]

How do you know he didn't mention Jesus more?

Such a mention would have to be in those portions of his works that did not survive into the modern era; however, no such quotes exist among the pre-Nicene Church fathers that allude to such "missing quotations", which means that the only references from Josephus about Jesus are the ones that are available today.  In any case, it is clear that Josephus was clearly unimpressed with Jesus and his so-called "miracles", just as he was unimpressed with the so-called Roman and Jewish miracle-workers.

Josephus knew of no Jesus. There was no reference to Jesus in any of his works until Eusebius of Caesarea "found" a copy with them c. 325 CE. Unfortunately for christians Eusebius was a well known forger and liar for god, having been called out for it in his own time by Origen. And we have plenty of evidence that the testamonium is an outright forgery, for example Photius I, patriarch of Constantinople had an original copy of Josephus in Hebrew which contained no reference in the 10th century, and Erasmus read multiple copies as late as the 1500s in Hebrew without any reference to Jesus. Added to this a stylistic analysis of the passages "witnessing" Jesus are written in terse and direct language, which was not the style of Josephus who would write 20 when one would do, and included minor and incidental details all over his works.

As I said Josephus knew of no Jesus.