Neither. Seeing is knowing.
For example, if I come to you with a closed fist and tell you "I have a diamond in my hand". You would have to choose to believe or not believe. But you would not KNOW. When I opened my hand and revealed the truth, believing would stop because you would then SEE. You would then KNOW. Once you see, you no longer believe.
For example, if I come to you with a closed fist and tell you "I have a diamond in my hand". You would have to choose to believe or not believe. But you would not KNOW. When I opened my hand and revealed the truth, believing would stop because you would then SEE. You would then KNOW. Once you see, you no longer believe.