Student or Learner
Hello, which sentence is correct, better:
(1) He had lost his wallet, and because of that he couldn't...
(2) He had lost his wallet, and because of this he couldn't...
On the other hand, I'd prefer "this", since the reason has just been referred to a few milliseconds before the choice of "this" and "that" is called for, and you can't get much more proximate than that.
But it might depend on the wider context. They're both right.
I agree that both can be used. However, personally, I favour:
He had lost his wallet, and consequently he couldn't...
He'd lost his wallet and so couldn't ...
For physical nouns, usage is more straightforward since it's the distance from the speaker that determines whether to use this/that or these/those - 'this book here'/'that book over there' - but with abstract nouns there is a less clear sense of distance.
Usually, the pronoun refers to something that has just been mentioned and 'this/these' are more often used since there is 'no distance' between the noun and the pronoun. If you try googling phrases like 'because of this/that', 'in these/those circumstances', 'under these/those conditions' you will find a preference for this/these - note 'preference' since both are fine in most cases.
One point to add: when talking about things that happened in the past we generally use that/those because the event is 'distant' in time:
"Back in those days couples stayed together and worked through their problems, buttoday everyone would rather get a divorce"