You can create local anchors in your pages and posts using the Anchor button.

Simply go to the point in the article where you’d like to create a local anchor, click the Anchor button, and give your anchor a name.

To link to that anchor, just create a link that goes to a pound sign ( # ) followed by whatever you named the anchor.  For example, if you created an anchor named “philosophy”, you’d enter “#philosophy” for the link to it.