The terms are arbitrary and don't relate to human memory. Using the term "I know this" is a post-hoc retrofit to a process exclusively accessed wordlessly. Just as "I remember this" does not access that process, but rather comments on the aftermath pretty unscientifically, like a sportscaster trying to read a pitcher's mind.

“We refute (based on empirical evidence) claims that humans use linguistic representations to think.” Ev Fedorenko Language Lab MIT 2024