Frustration Part II
Not all silent letters are completely redundant:
Silent letters can distinguish between homophones, e.g. in/inn; be/bee; lent/leant. This is an aid to readers already familiar with both words.
Silent letters may give an insight into the meaning or origin of a word, e.g. vineyard suggests vines more than the phonetic *vinyard would.
Silent letters may help to put weight on a certain syllable, telling the reader to put more stress on the syllable (Compare physics to physiques). The final ⟨fe⟩ in giraffe gives a clue to the second-syllable stress, where *giraf might suggest initial-stress.
Silent letters arise in several ways:
Sound changes occurring without a spelling change. The digraph ⟨gh⟩ was pronounced [x] in Middle English in such words as light.
Sound distinctions from foreign languages may be lost, as with the distinction between smooth rho (ρ) and roughly aspirated rho (ῥ) in Ancient Greek, represented by ⟨r⟩ and ⟨rh⟩ in Latin, but merged to the same [r] in English. Similarly with ⟨f⟩ / ⟨ph⟩, the latter from Greek phi.
Clusters of consonants may be simplified, producing silent letters e.g. silent ⟨th⟩ in asthma, silent ⟨t⟩ in Christmas (in Conservative RP, such as that spoken by Dame Vera Lynn, the ⟨t⟩ is pronounced - /krɪstməs/, instead of /krɪsməs/ in all other dialects). Similarly with alien clusters such as Greekinitial ⟨ps⟩ in psychology and ⟨mn⟩ in mnemonic, and the much rarer clusters in chthonic and phthalate.
Compound words are often simplified in pronunciation, while their spelling stays the same. For example, cupboard and breakfast were once pronounced as written, but were then simplified over time. The words forehead and waistcoat have largely reverted to their spelling pronunciations, but were once pronounced forrid and weskit, respectively.
Occasionally, spurious letters are consciously inserted in spelling to reflect etymology (real or imagined). The ⟨b⟩ in debt and doubt (from French dette, doute) was inserted to match Latin cognates like debit and dubitable. A silent ⟨s⟩ was inserted in isle (Norman French ile, Old French isle, from Latin insula; cognate to isolate) and then extended to the unrelated word island. The ⟨p⟩ in ptarmigan was apparently suggested by Greek words such as pteron ('wing').
Since accent and pronunciation differ, letters may be silent for some speakers but not others. In non-rhotic accents, ⟨r⟩ is silent in such words as hard, feathered; in h-dropping accents, ⟨h⟩ is silent. A speaker may or may not pronounce ⟨t⟩ in often, the first ⟨c⟩ in Antarctic, ⟨d⟩ in sandwich, etc.
