Mental telepathy is defined as "Communication through means other than the senses, or thought transference." This is a rather dry way of putting it, but is an accurate definition nonetheless. Solid proof as to whether telepathy is even a valid phenomenon has been extremely elusive over time, despite continuing efforts. Most evidence is anecdotal and therefore not accepted scientifically.
Having said that, most of us have had a telepathic experience at some point whether we realized it or not. Lots of things happen in life that we attribute to coincidence or chance that may actually be telepathic manifestations. Just because we can't prove it at this time, doesn't mean it doesn't exist. There are many things related to the mind, thought processes, and spirit that we still know little or nothing about. We know that thoughts are a type of energy, but we don't know much about how that energy originates or how it is dispersed. It could be that we are tapping into the theorized global consciousness, with our thoughts going out into a network to finally make their way to their destination, much like the phone network. Or it could be that we can actually focus thoughts like a laser beam at a particular receptive individual, whether they are aware of the process or not.
Anecdotal evidence of telepathy is really quite overwhelming, even if we can't come up with a repeatable scientific test to confirm it. The mother who is instantly aware that her daughter has had an accident, the person who thought about someone they haven't seen in years, then runs across that very person in a supermarket the next day, the strong feeling that the phone is about to ring, and then it does - all of these are likely manifestations of telepathy. As human beings, we are interconnected in ways that we don't fully understand, and therefore, it stands to reason that telepathy is as natural as breathing, but is for the most part stifled in our modern world with all it's distractions.
In my research for this topic, I encountered conflicting theories on how far we can actually go telepathically. It's pretty clear that we can wittingly or unwittingly transmit or receive messages, especially in times of stress or crisis. But can we influence that actions of others by thought transference alone? Hard to say but I think those with a strong motivation probably can.
Whether we can influence other people by thought alone. In my experience, the answer is yes, to a point. I don't think you can will someone to commit murder or jump off a cliff telepathically, but I do believe strongly that you can influence someone to think about you and possibly call or come by if you feel strongly that you want to see them. This would obviously have to be someone you had a fairly close emotional relationship with at some point in time, like an old boyfriend or girlfriend. It takes persistence and concentration, but not an enormous amount of energy such as what it would take to bend a spoon telekinetically. Just think of them often and concentrate on them. If you pass near their house in your car, call out their name. Visualize their face and call their name as you go to sleep at night and say Call Me! Imagine that your thoughts are a laser beam and point them in the direction of their house. Do this consistently and don't be surprised when the phone rings or they knock on your door within a month or so. Again, try this. If you are serious and persistent, it should work for you. One word of caution, though - be careful what you ask for.