In addition to biological limitations, our previous experiences and biases affect how we process and interpret information, a process that further distorts the accuracy and completeness of the information. An example of how experience can limit their ability to process information includes a study by the Indiana University School of Medicine of the influence of violent video games on mental activity. According to the study, young men who played violent video games for a week showed reduced activity in the region of the brain that controls emotion and aggressive behavior, a change that reversed itself when the men stopped playing for a week ("Violent Video Games..."). But even these results might not be accurate or complete, considering the possible influence of the study's source of funding (The Center for Successful Parenting), lurking variables such as the environment's influence (playing at home vs. in a lab), and the study's small sample size.

Even science acknowledges the limits of human knowledge. Economist Deirdre McCloskey summarized science studies since Kuhn by stating that "scientists are human speakers," and physicist Niels Bohr once said that physics "is what we humans can say about the physical world" (186). These statements echo Kenneth Burke's claim that even the sciences are ultimately subjective and therefore rhetorical. And since all communication is rhetorical, we should always analyze the communicator's intent and the communication's effect (Bizzell and Herzberg 14). Acknowledging the limits of our knowledge allows us to recognize our own limitations and biases and ultimately correct our beliefs based on new information.

Find out about rhetorical literacy.