When a well-respected animal scientist told me that animals do not think, I replied that if this were true, then I would have to conclude that I was unable to think. He could not imagine thinking in pictures, nor assign it the validity of real thought. Mine is a world of thinking that many language-based thinkers do not comprehend. I have observed that the people who are most likely to deny animals thought are often highly verbal thinkers who have poor visualization skills. They excel at verbal or sequential thinking activities but are unable to read blue-prints.
It is very likely that animals think in pictures and memories of smell, light, and sound patterns. In fact, my visual thinking patterns probably resemble animal thinking more closely than those of verbal thinkers. It seems silly to me to debate whether or not animals can think. To me it has always been obvious that they do. I have always pictured in my mind how the animal responds to the visual images in his head. Since I have pictures in my imagination, I assume that animals have similar pictures. Differences between language-based thought and picture-based thought my explain why artists and accountants fail to understand each other. They are like apples and oranges.
[More blog posts related to Temple Grandin and her work.]