Often those who are seeking solid proof regarding things such as psychic abilities do so with the idea that if someone else demonstrates said ability it will convince that it is real. The problem with this is usually unless we experience something for ourselves then we lack the ability to fully believe it is real. Sometimes we refuse to believe in it's existence even if we experience it for ourselves.
When I first began awakening to my own psychic abilities, I had a hard time accepting and believing that what I was experiencing was really happening. I must have tested myself hundreds of times in various situations and with various methods before I finally accepted that what I was experiencing was indeed real.
Eventually, I made it my mission to prove myself to other people as well. This helped to validate my own belief in my abilities as well. As I went around demonstrating my new found abilities to my friends and family, I soon realized that it was much easier to teach them to open to this different way of perceiving the world around them. So instead of proving myself to them by demonstrating what I could do, I showed them what they could do.
I learned through this experience that everyone has the same unlimited potential and that they need only to realize it to utilize it.
After I developed my own abilities a bit further, I began coaching and training others who were wanting to awaken and develop their higher senses.
Belief has much to do with our ability to access these "gifts", but it is not the only factor involved. There are other factors that can also limit our capability of accessing this part of ourselves. Diet, environment, daily habits, chemicals such as drugs and alcohol, our default attitude and state of mind also play a major part. No one thing can completely prevent a person from accessing their higher abilities but each of these factors can play a part.
It is not a matter of morality or purity of being that enables or prevents the use of these abilities, rather it is our self conceptualization of how we see and judge ourselves based upon our own personal belief systems and the ones that we allow others to force upon us. Ultimately, it is what we feel about ourselves and how strongly we allow ourselves to believe in our own abilities that determines how much of and in what way our true unlimited potential is realized. It is a matter of recognizing and releasing self-limiting beliefs.
I like to use the analogy of releasing the weight of sandbags from the basket of a hot air balloon. The more of these burdensome beliefs and ideas that we release, the lighter we become, the truer we are, and the brighter we shine as we ascend ever closer to true clarity of consciousness.
It is easy to tell if your beliefs are a burden or not. If your ideas and beliefs are something that you feel you need to cling tightly to and force upon others then you should definitely release them.
If your beliefs fill you with the truest purest essence of love and joy and you feel no need to prove your ideas to others or make them believe then you are ascending to truth and existing close to purest essence.