Is it lame to cancel on someone for hopes of being with someone else?

My friend set me up on a date tonight. This person met me before apparently and i might know the identity of this person because i know some people cant keep a secret. Apparently this person likes me alot hence the great efforts but im totally uninterested at the moment eversince i might have a chance with someone else i have been thinking about. My fortune cookie said i would meet my soulmate. And the fortune teller last fall said the same thing. So now im confused. I thought this person from CA was my soulmate & then i get gestures that the one i had my eye on might indeed be the one. Im a pretty shrewd person and all logic tells me to follow my heart.