As a web developer, I often find myself working with different non-professional self-called designers. In such situations, I often have to explain them the most basic rules and principles about the design in general and web design in particular. It is boring and unpleasant, especially if the self-called designer replies by "I never heard about those rules; prove that you're right".
Is there an authoritative reference (and not a blog of some unknown guy) which lists the basic rules and principles that every designer must learn at the very first year in college?
Remark: I thought about finding a good manual, but the designers I work with are usually unwilling to read books, so it's not a solution. I would rather imagine a website with a list of rules with a short description for every rule and the detailed links for people who want to go further or understand the reasons behind a precise rule. This being said, I'm also interested in books if they are accessible and easy to quote later in mail to illustrate what I've said during the discussion.
Example of rules I'm talking about:
In design, dark gray text on black background may be difficult to read.
In web design, you can't predict the size of the text, pixel by pixel, in browser, since it depends on the installed fonts and browser accessibility settings.