I've got it!
[video=youtube;dAE7uOO_4v4][/video]
No matter how much he wants to say and believe that the pen is red, Fletcher knows that he believes it to be red (in this case a factually correct belief).

If somehow we could analyze his stream of thoughts we'd be able to see that the first thing he identifies after noting the object is a pen is that it's blue. He didn't choose to do so he simply does.