The National Post explains hermeneutics
In the 19th century it was mainly a system of interpreting Christian teaching. Martin Heidegger, the modern philosopher who most deeply influenced Gadamer, helped to broaden it and insert it in the curriculum of modern philosophy.
Heidegger once wrote: “Language speaks.” Certain words and phrases can be infinitely expandable, opening fresh possibilities by their very existence. In Gadamer work, hermeneutics became one such word. It bulged with meanings, implications, speculations.
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In one of the interviews, Grondin quoted a remark that Heidegger made in a letter: “Hermeneutical philosophy? Oh, that is a Gadamer thing.” Gadamer never decided whether that was a compliment or not but in any case he continued to place this subject — enormously complicated, endlessly promising — at the core of his life as a philosopher.