Relationships are transactional, i.e., a transfer occurs based on mutual action between two (or more) people. That which transfers may be tangible or intangible. For example, if I cook a meal for a friend, and, in turn, my friend answers the questions I have about string theory, something tangible (food) and something intangible (information) transfers or is exchanged. Thus, naturally, I try to seek relationships with individuals who have something of value to transfer. Of course, many people are alarmed to hear this explanation. The word "user" comes to their mind, and if they should dare to imagine themselves in such a situation, the urge to shun the feeling of selfishness overwhelms them to the point of pure denial, denial that their friendships are based on self-interest. However, I say transcend the delusion. We all seek that which is beneficial and avoid that which is not. Ultimately, it is helpful to recognize that there is a degree of self-interest in everything we do. To know it and to control it would make us better masters of ourselves.