The reason... is so that

They are all OK.

English 1b3b. The reason I arrived early is so that I could leave early

This one is ungrammatical. "The reason ... is so that" doesn't work semantically. Leaving early IS the reason; "so that" doesn't come into it.

CJ

English 1b3b. The reason I arrived early is so that I could leave early

There are many examples of this pattern in the American Corpus. Here are some taken at random:

The reason we go through the lawyers is so that we don't have these meltdowns and emotional scenes.
The only reason I'm going down there is so that they can make me better,
Th

CalifJim English 1b3b. The reason I arrived early is so that I could leave earlyThis one is ungrammatical. "The reason ... is so that" doesn't work semantically. Leaving early IS the reason; "so that" doesn't come into it.CJ

This is was what I thought. I suppose it is often said and written in this way incorrectly - like how this is often said:

The re

AlpheccaStarsThere are many examples of this pattern in the American Corpus.

None of those example were generated by me, I hope!

CalifJimBy the way, have you checked the frequency of "... reason ... is because ..."?

No, I haven't compared the two.

The ones I posted were from news programs (CNN, ABC, NBC). I picked three out of the first 100 hits..

This one is from Popular Mechanics, a mainstream magazine:

And the reason is so that we can seamlessly operate wi

Google books shows 9,820 results for "the reason is so that" and 24,800,000 for "the reason is that."

I don't think showing proof of this wording being used in published books or any credible source really helps all that much though. Unfortunately, I am unable to analyze the syntax and answer my own question.

English 1b3I am unable to analyze the syntax and answer my own question.

The problem is not syntax; it's semantics.

Consider:

The condition is so that ...
The situation is so that ...
The purpose is so that ...
The circumstances are so that ...
The fact is so that ...

And , of course,

The reason is so that ..

CalifJimConsider:The condition is so that ...The situation is so that ...The purpose is so that ...The circumstances are so that ...The fact is so that ...And , of course,The reason is so that ...

Thanks. I'm sold.

The reason I arrived early is that I wanted to leave early.

Without further context, I'd be more comfortable with -

The reason I arrived early was that I wanted to leave early.

Clive