Is it idiomatic to say, 'someone thinks about how XXX' instead of 'someone thinks XXX'?

Question

Suppose in a windy day, a billboard fell to the ground and John saw that. Instead of saying,

John thought it could knock him out instantly if it hit him

is it idiomatic to say this?

John thought about how it could knock him out instantly if it hit him

The second sentence sounds kind of weird to me, since 'how' usually means 'in what way or manner; by what means'. So, the second sentence feels a bit like 'John thought about/imagined the (different) way(s)/process(es) the billboard could have knocked him out'. Yet, I heard it used as an equivalence to 'think + XXX' in a video, speaker of which is not sure to be a native speaker.

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Postscript: As is pointed out by @bakunin, I may need to use the perfect tense here. So, the quoted sentence above should be changed to the following two, respectively.

John thought it could have knocked him out instantly if it hit him.

John thought about how it could have knocked him out instantly if it hit him.

Is the second sentence in this postscript idiomatic?

Answer 1

To think about something is a conscious action, while to think something is a state of having some notion, opinion, or accepting something as fact:

I thought about Lateralus being an awful album. / I thought about how Lateralus is an awful album. (At some point in the past, I spent some time consciously having that thought. I might still consider it an awful album, but I no longer have it on my mind)

I thought Lateralus was an awful album. (At some point in the past, I had an opinion that it was an awful album - although I might not have spent much or any time with that opinion on my conscious mind.)

In your example, John thought about... indicates that John was actively thinking about it - imagining it, etc., generally spending some time considering that scenario. John thought... indicates at best a quick thought crossing John's mind, and possibly just says that John knew that it was the case.

Answer 2

If you think about something, you are considering it in detail with all its implications. John may just have had a passing thought "That could knock someone out", or he could have said to himself "If that had hit me, I would have been taken to hospital and wouldn't have been able to pick up my children from school."

Answer 3

Your feeling that the second sentence sounds weird is quite justified. It uses the wrong tense:

John thought about how it could have knocked him out instantly if it had hit him.

This is a case of "reported speech": Johns thoughts are the supposed speech (he thought: "if that hit me id'd be knocked out." and these thoughts are reported.

Notice that even a question in reported speech is not a question any more (the report of a question is a factual statement), so there is no question mark at the end:

He asks: "what time is it?"

but

He asks what time it is.

Answer 4

John thought the wind could knock him out = John's opinion. As far as John knows, the wind might or might not be capable of knocking him out. He knows he could be wrong, but he's inclined to think it's possible. The sentence is about the fact that John believes this.

John thought about how the wind could knock him out = taken as fact. John believes fully that it's possible for the wind to knock him out and would not expect anyone to dispute it. The sentence isn't about this at all, which is why we assume it so we can focus on what John is actually thinking, i.e. wherever this supposition leads him (maybe we're supposed to imagine that ourselves).

Answer 5

'How' can be used as 'that'.

Part of the definitions of 'how' given by The Free Dictionary:

conj. That: I told them how I had once been bitten by a snake.

conj. Informal. that: She told us how he was honest and could be trusted.

adv. not standard Also: as how that: he told me as how the shop was closed.

Answer 6

"think" (or "thought") by itself means to simply have a thought that what follows is the case.

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"think about how" could mean either "think that" or "think in what way". That leads to the following usages:

• To have a thought that something is the case (e.g. "think about how he didn't get his paycheck yet").

  This is generally idiomatic.

  Note that the example above would fall exclusively under this meaning, and could not also mean thinking about the reasons for him not getting his paycheck (that would be "why" instead of "how").

  There is a notable difference between "I think about how he didn't get his paycheck yet" and "I think he didn't get his paycheck yet": the former involves thinking about the fact that he didn't get his paycheck yet, while the latter means you're somewhat sure he didn't get his paycheck yet.

• To have a thought that something could be the case (e.g. "think about how the car could hit him").

  This is not an uncommon usage, but it's little more than a more verbose version of just "think", so I would recommend against using it.

• To have thoughts about in what way something is the case (e.g. "think about how rain works").

  This is perfectly idiomatic.

• To have thoughts about in what way something could be the case (e.g. "think about how the car could hit him").

  There's nothing explicitly wrong with this usage, but I'd generally phrase it differently if I wanted to convey this specific meaning, since it's typically ambiguous whether one means this, or simply that something is the case (as in it is the case that the car could hit him, for the example above).

• To consider what the answer to a question might be (e.g. "think about how much it would rain").

  This is perfectly idiomatic. In the above example, what you're thinking about is "how much it would rain". So it's more "think about" + X, and not "think about how" + X.