Wordpress Canonical Tag Pointing to Same Page

[WebServiceConsulting.com]

So I noticed on a few of my clients wordpress tags (via moz) that there are canonical tags on URLs, pointing to that same URL.

What is the point of that, and is it harming the website? Is this being done automatically via a plugin?

Should I remove the canonical tags or leave as is?

[Schwaab]

There may be a plug in to place rel=canonical tags on the page.  Sometimes, when the plug in field is left blank, a self referencing rel=canonical tag is placed on the page.  I wouldn't worry about it too much, it shouldn't harm your site.

From: http://moz.com/blog/dispelling-a-persistent-rel-canonical-myth

"Looking through Google's blog post on the subject, this isn't explicitly stated. However, you can see that even the example website, Wikia, employs this practice on the page Google points out. You can also see Googler Maile Ohyeanswering a comment on this:

@Wade: Yes, it's absolutely okay to have a self-referential rel="canonical". It won't harm the system and additionally, by including a self-reference you better ensure that your mirrors have a rel=”canonical” to you."