Simple Wordpress AJAX pagination

You're using jQuery's load() method to insert content, which is a shortcut for $.ajax, which of course inserts the content dynamically.

Dynamic content requires delegation of the events to a non-dynamic parent, something jQuery makes easy with on()

jQuery(function($) {    $('#content').on('click', '#pagination a', function(e){        e.preventDefault();        var link = $(this).attr('href');        $('#content').fadeOut(500, function(){            $(this).load(link + ' #content', function() {                $(this).fadeIn(500);            });        });    });});

I used adeneo's solution, with a couple of minor tweaks.

1. My pagination was outside of the container that I wanted to load, so I performed a separate call for the pagination content. Per the comments, I've updated the code to make a single Ajax call, filtering on the returned data to retrieve and update the desired elements.
2. My pagination consisted of all links, even for the current page. There was no point in doing an Ajax request if the clicked element is the active page, so I added logic to target only pagination links whose parent list item element did not have the .disabled class.
3. The page jumped every time I loaded new content because it was using fadeOut/In (which sets display: none; once the opacity animation is complete). Instead, I manually animate the opacity, which limits the amount of height fluctuation.

Here's the updated code:

$('#content').on('click', '#pagination :not(.disabled) a', function(e){    e.preventDefault();    var link = $(this).attr('href');    $.post( link, function( data ) {        var content = $(data).filter('#content');        var pagination = $(data).filter('#pagination');        $('#pagination').html(pagination.html());        $('#content').animate(            {opacity: 0},            500,             function(){                $(this).html(content.html()).animate(                    {opacity: 1},                    500                );            }        );    });});