A long standing proposition for many within the magical community (both past and present) has been that belief in the efficacy of magic is a necessary prerequisite for any magical operation to be successful. With just a little bit of reading one can see that this proposition is upheld by both traditional and non-traditional magical practitioners alike. Yet, my personal success at attaining results through magical technique devoid of belief in the efficacy of magic clearly demonstrates (to me at least), that belief is not a necessary element for magical success. Interestingly, there was even one occurrence (during a particularly "dangerous" evocation) where I was afraid that the magic might work that I attained some incredible results. It should be pointed out that I did not "disbelieve" in the utility of magic, but rather held to the notion that it might be effective. I'm not sure if magical success can be had while disbelieving its efficacy, but I am convinced that non-belief in magic while leaving open the possibility that it might work does not ensure failure.(Interestingly, it is my magical successes (devoid of a belief in the utility of magic) that has begun to nurture a belief in the power of magic to bring about results.)
So, I say, give magic a try even if you have doubts about the ability of magic to manifest your desires. As long as you leave enough room in your head for the idea that magic might work, you may just be surprised at the results.