Escaping quotation marks in PHP

Question

I am getting a parse error, and I am assuming that it's because of the quotation marks over "time". How can I make it treat it as a whole string?

<?php
    $text1 = 'From time to "time" this submerged or latent theater in 'Hamlet'
    becomes almost overt. It is close to the surface in Hamlet's pretense of madness,
    the "antic disposition" he puts on to protect himself and prevent his antagonists
    from plucking out the heart of his mystery. It is even closer to the surface when
    Hamlet enters his mother's room and holds up, side by side, the pictures of the
    two kings, Old Hamlet and Claudius, and proceeds to describe for her the true
    nature of the choice she has made, presenting truth by means of a show.
    Similarly, when he leaps into the open grave at Ophelia's funeral, ranting in
    high heroic terms, he is acting out for Laertes, and perhaps for himself as well,
    the folly of excessive, melodramatic expressions of grief.";

    $text2 = 'From time to "time"';

    similar_text($textl, $text2, $p);
    echo "Percent: $p%";

The problem is that I can't manually add \ before every quotation mark. This is the actual text I need to compare.