Do you say "one can only imagine"? What does it mean?

I encountered the same expression twice in different chapters of the same book. I guess it mean "You can hardly imagine". Can you please explain it to me?

Quote:

One can only imagine a household where two totally diverse cultures intersect.

One can only imagine the stresses experienced by those trying to make up for lost time by condensing ten years of their lives into a few hectic years.

According to the context, I figure it means "You can hardly imagine". But I Googled this expression but didin't get many hits so I'm kind of confused by this expression. Do you say it? And what does it mean exactly?

I encountered the same expression twice in different chapters of the same book. I guess it mean "You can hardly imagine". Can you please explain it to me?

Quote:

One can only imagine a household where two totally diverse cultures intersect.

One can only imagine the stresses experienced by those trying to make up for lost time by condensing ten years of their lives into a few hectic years.

According to the context, I figure it means "You can hardly imagine". But I Googled this expression but didin't get many hits so I'm kind of confused by this expression. Do you say it? And what does it mean exactly?

KatiMorton"one can only imagine"Yes. It is a fixed expression.

Grandmother: Little Johnny has been using the computer for six hours without stopping. I wonder what he is doing?

Grandfather: One can only imagine!

(Grandmother and Grandfather do not know how to use the computer very well. They don't know about computer games or other forms of entertainment. They have no idea what Johnny is doing. They have to imagine what is so interesting about it.)

Comments

KatiMortonYou can't do anything else except use your imagination, because you are ignorant or have no experience with the subject.

AlpheccaStarsThis was a putdown a high society woman might use. She's saying it's impossible to imagine herself stooping so low. or being so low class. Mildred did what? One can only imagine what she'll do next!

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