About the only time you should bathe a cat, is if it got into something icky like lots of mud, oil, or some other grime that they can't get out themselves.
With a long haired kitty like Prince, it might be best to get a CAT shampoo with a bit of conditioner in it, just so it's easier to brush out tangles.
With a long haired kitty, it's best to brush them a lot... once a day would be preferable (some cats LOVE it) or at least once a week (if he's like Paizly and hates it), just to make sure it doesn't get all matted up. If it gets too matted, you'd have to end up shaving him! Mats aren't just annoying...depending on how bad they get, they can actually end up hurting (for the outter hairs pulling in with the inner mess), leaving chunks of skin exposed, and other various issues.
I agree with the Dawn. Since they use it on wildlife in oil spills, it should be safe for kitty... in small amounts (probably only a few drops), and rinsed out completely!
And the warm towels fresh from the dryer, too! While I doubt he'd actually get hypothermia from a bath (especially if you use very warm water), it still isn't pleasant to get chilly from being wet too long.