What are the differences between "so + adj+ that" & "too + adj + that" / "so + adj" & "too + adj"?

Question

See these:

The music is so loud!

The music is too loud!

The music is so loud that I can't sleep.

The music is too loud that I can't sleep.

What are the differences between "so + adj+ that" & "too + adj + that" / "so + adj" & "too + adj"?

This website say:

As an adverb, so is an intensifier. It intensifies, or makes stronger, the adjective or adverb that follows it.

So is used like very, but so is a much stronger exclamation.

Too can be used the same way as so, but it has a completely different meaning.

Too is an intensifier that is used to mean more than needed, more than necessary, or more than enough. It is a negative expression

So, "So" can be used in positive & negative sentences? but "too" can be used in negative sentences only?

He is so smart (ok?)

He is too smart (not ok?)

He is so stupid (ok?)

He is too stupid (not ok?)

This site said:

Too: excessive & so: a lot

People use too many plastic bags. (excessive)

People use so many plastic bags. (a lot)

People drive too many large cars. (excessive)

People drive so many large cars. (a lot)

People use too much fuel. (excessive)

People use so much fuel. (a lot)

People spend too much time in traffic (excessive)

People spend so much time in traffic. (a lot)

Answer 1

Look at so in this context this way:

1. By itself, it is an emphatic form of very.

She is so smart!

This means she is smart enough that you are impressed and want to extol her intelligence.

2. In the so ... that it becomes a qualifier.

She is so smart that she just won a scholarship to Princeton in physics.

Here it offers evidence for your conclusion. How smart is she? Smart enough to win a scholarship to Princeton in physics. Put in more words, this one means

She is smart to the extent that she has just won a scholarship to Princeton in physics.

Often the construction is used as a simple intensifier.

He's so mean sometimes I just can't believe it.

Translation: He's really, really mean.

This is an important construction in English. It's so important, in fact, that you need to get a handle on it as soon as possible.

Too is usually, but not always, negative. It can be used as a simple intensifier.

You are just too good!

This means you are very, very good.

Answer 2

The music is so loud!

The music is too loud!

It sounds like you already have a good understanding of the differences here. The first is just saying the music is very loud while the second says the noise is in excess.

The music is so loud that I can't sleep.

This gives a more precise measure of how loud. "...So ____ that..." is a very common construct that tells us a result of this quality. You can also drop the word "that" and be understood in the same way: "The music is so loud I can't sleep."

This serves the purpose of qualifying 'so'.

• "He was so late."
• "How late?"
• "He was so late that he didn't just miss the opening credits, he missed the entire movie."

The music is too loud that I can't sleep.

This is not grammatical. Instead of "that" here we use "for." So this sentence ought to read, "The music is too loud for me to sleep."

(Note: "For" is used when the word following is a noun or adjective, while "to" is used when it is a verb or adverb.)

You can drop "for" here as well, but instead of leaving the sentence unchanged this breaks it into two independent clauses which requires rewording the second half. "The music is too loud; I can't sleep."

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In relation to too being negative, this is often but not necessarily true. We have a saying in English that too much of a good thing is bad to sum this up -- whatever you have too much of, even if it's something positive, having it in excess is undesirable.

However, that does not mean you can only use it in a negative way, or even only use it with a negative adjective. Both your examples of "he is too smart" and "he is too stupid" are fine.

He may be too smart or too stupid for a specific purpose.

"He is too stupid to notice we're making fun of him."

Clearly this is negative. Nobody wants to be stupid, nor to be made fun of without noticing.

"He is too smart to be fooled by that."

This, on the other hand, is not negative. Nobody wants to be fooled either, so being too smart for it is a good thing.

The other non-negative way it's used in English is a bit idiomatic, but it's used in the same way "so" or "very" might be. Sentences such as "you are too kind" are not uncommon (although maybe a little bit old-fashioned), but they have an implied humbleness to them that makes it read a bit more like "you are kinder than I deserve." In this usage it will always be used with very obviously positive adjectives.