There are two main opposing grapheme concepts. In the so-called "referential conception", graphemes are interpreted as the smallest units of writing that correspond with sounds (more accurately phonemes). In this concept, the "sh" in the written English word "shake" would be a grapheme because it represents the phoneme ʃ. This referential concept is linked to the "dependency hypothesis" that claims that writing merely depicts speech. By contrast, the "analogical concept" defines graphemes analogously to phonemes, i.e. via written minimal pairs such as "shake" vs. "snake". In this example, "h" and "n" are graphemes because they distinguish two words. This analogical concept is associated with the autonomy hypothesis which holds that writing is a system in its own right and should be studied independently from speech. Both concepts have weaknesses.