Bind submit() Function After Load() function (jQuery)

I'm using jQuery's load() function to change content on a page dynamically. It's a application with different 'levels' but the URL never changes.

It's working fine except for the final screen I'm using. I've got a form with text inputs etc that I need to create some form validations for but I can't get on('submit') to work after the page load. I am using a callback function on the load function and I do run some simple jQuery CSS, etc. to content that is on the final_page.php so I know that it's successfully running the function AFTER the content is loaded.

I'm trying to simply just apply a preventDefault() to the form for now to confirm that it's working correctly but the form submits every time I get to that final page so it looks like the on() function doesn't get bound to the form selector.

Is there some sort of conflicting with submit and load?

$('#main_content').load('final_page.php', function(){
    $('#main_content').css({'height':'auto','padding-bottom':'25px','background':'#086c8c'});
    $('#hidden_input').attr('value', 'complete');

    //GOOD UP TO THIS POINT

    $('#final_form').on('submit',function(e){               
        e.preventDefault();
    });
});