The sense of dumb meaning “stupid” is much more recent in English than the sense of “lacking the power of speech.” However, the later sense has overwhelmed the earlier to such a degree that any reference to a person who cannot speak as dumb is clearly offensive. Indeed, dumb now has such strong connotations of dimwittedness that even using it of animals, as in the dumb creatures of the forest, is likely to cause either mirth or misunderstanding.
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But the offensiveness of a phrase such as deaf and dumb is due only in part to the confusion between the two senses of dumb. Equally objectionable is the implication that deafness is an insurmountable obstacle to acquiring speech, or, on the other hand, that vocal utterance is the only form of speaking. Whether with surgical implants to enhance residual hearing, through learning a signed language, or by a combination of these and other methods, deaf children today are far more likely than in the past to lead lives rich in communication and language, making any expression such as deaf and dumb or deaf-mute not only offensive but in most cases simply inaccurate.
