Hermeneutics is generally understood as the 'science' of interpretation. The scope of hermeneutics varies from hermeneutical school to school, but most include texts. Some, such as many in mid-to-late twentieth-century France (e.g. Jacques Derrida, Paul Ricoeur) extend their scope to include any and all acts of communication: symbols, speech, and even gestures.
Modern hermeneutics stems from a variety of sources, primarily from religion: all three of the monotheistic faiths have rules, principles and guidelines for understanding their scriptures. The 'father' of modern hermeneutics is generally ascribed to Friedrich Schleiermacher who first began to use hermeneutics separate and distinct from any kind of religious or Biblical context. He believed that the special hermeneutic practices (in law and theology) can be subsumed into a general, universal hermeneutic philosophy. Legal interpretation has led to rules and principles being set for interpretation. In the nineteenth and twentieth century, philosophers have tried to come to grips with what a hermeneutic approach means. These writers have tried to understand both how the rules for interpretation of texts is set, how they are practiced and tried to solve various problems that have come about in the interpretation of texts.
One of the problems with hermeneutics tries to deal with is what is called the hermeneutic circle. When reading a text, the only way to understand the text is through itself, which seems paradoxical: how can you understand a text if the only way to understand it is to already understand it? Schleiermacher solves this problem by suggesting that when we read a text, we engage in a 'cursory' reading, and then follow that up with a closer and more rigorous examination, trying to understand the text both on a grammatical and psychological level. The formal grammatical analysis is for straight-forward works, while more original or personal works require that "one, so to speak, transforms oneself into the other person and tries to understand the individual directly".
After Schleiermacher, Martin Heidegger continued the hermeneutical tradition, using the hermeneutical cycle to develop his own ontology. One of Heidegger's students, however, extended Heidegger's hermeneutics into a fully-developed method of interpretation. That student was Hans-Georg Gadamer and is perhaps the most important philosopher when it comes to understanding hermeneutics. Gadamer tries to recast hermeneutics in the philosophies of phenomenology and the work of Martin Heidegger - he rejects what he sees as dogmatic, Enlightenment reason, and tries to stake out ground for a distinctive hermeneutical 'human science'. Gadamer states that we all bring prejudices (or a pre-judgment - not a negative term in Gadamer's use) with us, set by our own traditions and beliefs, when reading a text, even if we think we do not. In reading a historical text, even if we attempt to understand it on it's own terms - the fact of our reading the text means that we pre-judge that it will be worth reading, and that we will reach a certain 'completeness' after reading it.
- Friedrich Schleirmacher, Hermeneutics and Criticism, p. 92