Remember?

One way in which verbs can vary between languages is if they are seen as having a point of completion. "Know", for example, doesn't ever "finish". It makes no sense to talk about being "done knowing" or "knowing it in 5 minutes" - "know" doesn't ever get done, so to speak. "Know" describes a state, rather than an action. "Learn", on the other hand, culminates in the point where something is committed to memory. You can be done learning, or learn something in 1 day. Once you know it, you're done learning it.

Both the verbs "to know" and "to remember" in Japanese have endpoints at the point where something is learned or memorized. Hence to say "I know that" in Japanese, you take the Japanese verb "shiru", and use it in something like the English perfect tense - "I have known it". This indicates that you have gained the knowledge, and hence "know" it now. As far as I am aware, there is no verb to describe having knowledge of something as a state.