need get posts() to only list 10 per page

I used the following code:

<?php
$args = array( 'numberposts' => -1 );
$lastposts = get_posts( $args );
foreach($lastposts as $post) : setup_postdata($post); ?>
	<h2><a>"><?php the_title(); ?></a></h2>
	<?php the_content(); ?>
<?php endforeach; ?>

[Please post code or markup snippets between backticks or use the code button.]

I do want to list all posts, however I only want to show 10 posts per page. It is listing all the posts on one page even though I have it set in the dashboard for 10 posts. Any help would be appreciated.

Thanks,
Todd