Is it common to say "the more is true"?

The sentence looks like a typo. The writer probably meant "the more it's true," which is to say "it becomes more true when I think about it more."

Furthermore, they probably actually meant something like "the more it seems true," or "the more I realize it's true," as thinking about something doesn't generally change its truth value. This kind of elision is common in informal speech, but still wrong.