Discussion Forum—A Way with Words, a fun radio show and podcast about language

I agree with Glenn:   This has to do with how "an historian" is pronounced.   I decided a while back that those who write "an historian" (and it's been going on for centuries, not years) pronounce it with the 'h': "an istorian".   If you write "a historian", mentally you're still hearing the 'h'.

Once I realized that, I decided that there's nothing wrong with 'an hypothesis', etc.   I don't know how I say it aloud, but I suspect it varies; I'm sure I've said "an istoric event" a few times.   I doubt I ever say or write "an hotel" or "an hostage", though.

In that case—to reprise a related topic—I imagine you would say "thee erb", not "thuh herb"?

There's a possibility that your two examples are unrelated, though, to the original discussion.   I don't say they are unrelated, because I'm not sure.   But look at it this way:   You (and I too) pronounce "herb" with a silent 'h'.   I always do, whether or not it's preceded by "an".   So it doesn't really relate to a question about people saying "hypothesis" with the 'h' but "an hypothesis" with the 'h' either silent or much weakened.

As for "Herbert", I'm not sure but I can't think of an example of "an" going before an h- word where the first syllable has the emphasis.   People write "an hypothesis", "an historian" and "an historic event", but do they ever write "an history"?   I don't recall ever seeing it.   Maybe the emphasis makes it impossible.   Just a thought.