Posted by R. Berg on March 10, 2003
In Reply to: Slow up slow down posted by psycholinguini on March 09, 2003
: Does anyone know any reason slow up and slow down mean the same? And where did each phrase come from? (I can end in a preposition here, can't I?)
Probably no one knows the reason, but this and similar paradoxes are recognized. The Oxford English Dictionary's entry for "up," adverb, several pages long, contains this: "Under the following heads are placed only those figurative uses which admit of being classified under some general concept. Further illustration will usually be found under the verbs most commonly occurring in the various phrases, together with many special uses which are confined to one or other of those verbs . . . . Some uncertainty attaches to the origin and development of many of these uses, the variety of which is so great that the adverb comes to present a number of highly divergent and even directly opposite senses, e.g. 'to bind up' (sense 19) in contrast with 'to break up' (sense 21 b)."
One sense of "up" is "To or towards a state of completion or finality. (Frequently serving merely to emphasize the import of the verb.)"
To put it another way, English is a patchwork of words and uses that arose at different times in history, and there's nothing to be done about it.