"I don't believe-I know".
-Carl Jung, founder of a neopsychoanalytic school, on the question of belief in 'god'..
Believe: 1 a : to have a firm religious faith b : to accept as true 2 : to have a firm conviction 3 : to hold an opinion
Know : 1 a (1) : to perceive directly : have direct cognition of (2) : to have understanding of (3) : to recognize the nature of : DISCERN b (1) : to recognize as being the same as something previously known (2) to be acquainted or familiar with (3) : to have experience of 2 a : to be aware of the truth or factuality b : to have a practical understanding
Believing is holding an opinion. Knowing is to have direct experience, to understand, and to have a practical understanding of some concept. To further delineate the two different terms, it is important to realize that while one can "make- believe", one cannot "make-know".