Q: I see no significant reason to have both “oblige” and “obligate.” Any subtle differences in meaning seem fatuous. The first version is sufficient to provide the sense of its usage. (I’m British, so I may be a bit of a pedant.) I’d love to hear your thoughts.
A: I’m obliged to you for your comments, but I disagree with you about those two words. They serve different purposes in ordinary usage, and in fact are treated differently by lexicographers.
The verb “oblige” (to bind by oath, contract, promise, etc.) dates back to 1325, according to the Oxford English Dictionary. “Obligate,” which came along in 1533, adds a moral dimension to the sense of obligation; it means to bind morally, or to put (a person) under a moral obligation.
Certainly there is some overlapping, especially in modern usage. The American Heritage Dictionary of the English Language (4th ed.), for example, says one of the meanings of both words is to cause to be grateful or indebted. But on the whole most people, I believe, use “oblige” and “obligate” differently.
We usually say “I was obliged to move,” not “I was obligated to move.” When we say “I am obliged to you,” we may simply mean “Thank you”; there is no moral imperative to do something in return. But when we say “I am obligated to you,” we imply a duty or responsibility to pay the debt back in kind.
Furthermore, when we say “Can you oblige me by doing such-and-such?” or “I can oblige you in this,” we are usually speaking of something done as a favor or an accommodation (in this sense, “oblige” is a synonym for “accommodate”).
So I think the subtle differences are enough to justify the two different words.
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