And I believe that generally, the more you travel, ...

[Nonverbis]

The book is "Upstream Proficiency" by Virginia Evans and Jenny Dooley.

Could you tell me whether a comma is missing here?

 

[Tarheel]

No. There is a comma after generally, where there should be one.

 

[5jj]

There should either be a comma before and after 'generally' or no commas.

 

[Tarheel]

There should either be a comma before and after 'generally' or no commas.

I've changed my mind, and now I agree with you.

 

[jutfrank]

There should either be a comma before and after 'generally' or no commas.

I disagree with both of your comments here. The punctuation is fine as it is. Why do you feel a comma is necessary after subordinating that? Why do you think that a comma would not be necessary after sentence adverbial generally?

 

[emsr2d2]

I have nothing against enclosing "generally" between commas purely because it is, after all, extra information.

 

[jutfrank]

I have nothing against enclosing "generally" between commas

Me neither. But a comma before it is unnecessary and a comma after it is necessary.

purely because it is, after all, extra information.

Not really. When you preface a sentence with a sentence adverb, it isn't really 'extra information'.

Generally, the more you travel, the more you begin to question your place in the world.

The word Generally here modifies the whole of the following comment. A comma is necessary after this kind of sentence adverb.

But the OP's question concerns whether there should be a comma before the word generally. I say there doesn't need to be. (That's not say that you can't put one there if you mean to tell the reader to make a pause.) If you remove the adverbial generally you can see the comma is unnecessary:

I believe that the more you travel, the more you begin to question your place in the world.

There's no need to use a comma after a linking that unless the writer deliberately aims to get the reader to make a pause in her speech. In this case, the sentence adverb generally belongs in the second clause, so it doesn't need to be preceded by a comma. The linker that is enough to introduce the new clause.

 

[5jj]

Why do you feel a comma is necessary after subordinating that?

I don't. I said that a comma was possible before and after 'generally'.

Why do you think that a comma would not be necessary after sentence adverbial generally?

If there is no comma before 'generally, I would not use one after it.