“For the interpreter to ‘perform’ the text, he must ‘understand’ it: he must preunderstand the subject and the situation before he can enter the horizon of its meaning. Only when he can step into the magic circle of its horizon can the interpreter understand its meaning. This is that mysterious ‘hermeneutical circle’ without which the meaning of the text cannot emerge.” (p25)
Palmer’s defining of the hermeneutic circle comes from building up out of pre-understandings and horizonality. To explain and experience the interpreter needs to understand the experience, which comes from testing and building from pre-understandings of similar experiences. From pre-understandings the interpreter can then focus interpretation from within a horizon of the experience, a context in which the meanings of how it is experienced are focused.