Disqus plug-in not showing

I installed the disqus plug-in and it does not show on my list of plugins, so I can’t activate it. Has anyone else had this problem? The other 11 plugins I use all work fine and I installed the Disqus plugin to the wp-content/plugins directory same as all the others. I’m using the Twenty Fourteen theme. Is this plugin not compatible with this theme maybe? Anyone else have similar issues?

http://wordpress.org/plugins/disqus-comment-system/