Is it possible to think without using words? Thinking in the most generalized case doesn't need to involve words... for example when I ask you to think about a horse... the first thing that appears in your mind is probably an image of a horse rather than a description of what a horse is... or the word HORSE. Words are simply the means to provide a symbolic representation towards ideas/objects... the way to store multiple experiences we have on a given topic. It appears to me to be a way to get around the limits of our mental processing capacity (working memory is 7 plus minus 2 objects). By labelling a huge list of experiences together as a symbol (one word), we can now start to relate different experiences/ideas together.
Here's a what-if scenario... What if our minds have unlimited processing capacity... do we still need language to think rationally? Feel free to completely bash this nonsensical idea if you feel like it... just provide justification for your thoughts.