Comments are invisible, what’s the problem with wp_list_comments?

I believe wp_list_comments needs to be inside the loop. If not, you need to pass an array of comments to it. You are doing neither of these.

Either move it inside your loop, or call get_comments() (as Johannes rightly points out) and pass the returned array from that into wp_list_comments as the second argument.

You also need to call comments_template() before trying to output your comments. You can pass this function the name of a file, or it will default to comments.php. This file will then be included. So, you should move your comments code into this separate file:

<?php get_header(); ?>
<div id="main-content">
    <section id="primary">
<!--    <h2 class="cat-title">Latest news</h2> -->
        <?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>

        <article class="post">
            <img src="">
            <h2 class="post-title"><?php the_title(); ?></h2>
            <?php the_content('Read More...'); ?>
            <div class="post-info">
                by <?php the_author(); ?>,
                at <?php the_time('l F d, Y'); ?></a>
            </div>
            <?php previous_post_link(); ?> / <?php next_post_link(); ?>
        </article>
    <?php comments_template(); ?>
        <?php endwhile; else: ?>
            <p><?php _e('No posts were found. Sorry!', 'magaziner'); ?></p>
        <?php endif; ?>



    </section>

    <?php get_sidebar(); ?>
</div>
<?php get_footer(); ?>

In comments.php:

<ol class="commentlist">
    <?php wp_list_comments(); ?>
</ol>
<?php comment_form(); ?>