Copying content from other sites?

What if you give permission for someone to copy something off your site wouldn’t that be hurtful to you also?

According to this below it would only seem logical to not even let your site be copied even with permission? So being a nice guy here can bite you in the butt, can that be true??

Stealing copy from other sites is not only ethically wrong and often illegal; it is also not doing you any favours in the search engine arena. Search engines like Google try to rank websites as usefully as possible. In order to provide the highest quality results to their users, they try to eliminate spam sites and non germane sites from their results page. If a Google-bot crawls your page and goes, “Hmm… this copy appears verbatim on 221 other pages,” it’s going to rank your site much lower than someone else’s site that has unique copy on it.

Yea google doesn’t know if you gave permission or not. I would highly discourage any cross posting or duplicate content scenarios. It will hurt you. Google is looking for fresh / authoritative content.

That seems to be the best way to go or at the very least get permission from someone instead of just hijacking there stuff.