Helping people gives us a sense of satisfaction.

[newkeenlearner]

Which sentences is better?

Helping people gives us a sense of satisfaction. This joy cheers us up more than the one receiving help.

Helping people can give us a sense of satisfaction. This joy may cheer us up more than the one receiving help.

 

[Charlie Bernstein]

Which sentences are better?

Helping people gives us a sense of satisfaction. This joy cheers us up more than it cheers the one receiving help.

Helping people can give us a sense of satisfaction. This joy may cheer us up more than it cheers the one receiving help.

See the corrections. They clarify your meaning. Without it, it could be read as "This joy cheers us up more than the one receiving help cheers us up.

And that's not what you mean. You're not saying that the person cheer us up. You're saying that helping cheers us up.