document.write not working in html

I am try to write inside html document. this is my javascript code:

<script type="text/javascript">document.write("Hello World!")</script>

I am working with chrome and get the following error:

Uncaught TypeError: Object # has no method 'write'

I tried alert method and it worked.

EDIT: this is part of a project in scala/lift that also uses jquery if that may hint something. I suspect document object is redefined. is there a way to know that / to access the original one?