The transmission of information is not limited to text or language---the human visual system has capabilities that allow us to absorb large amounts of information in parallel \cite[9]{victor}. This channel for information thus implies that images are an important way for us to learn about our environment.


``To the thinking soul images serve as if they were contents of perception ... [t]hat is why the soul never thinks without an image'' \cite[60]{aristotle}. This quote from Aristotle describes a theory for how humans process information; simply, thought is not possible without images in his view. Humans harness an innate ability to process visual information---visualizations enable high-bandwidth communication of ideas between humans \cite[309]{kamat}.


Beyond images are \emph{diagrams}---a structured representation of a concept or object with graphical components laid out in a simplified way. The properties of diagrams present information in a manner that allows the human visual system to process the data in parallel \cite[2]{diagrams}. There exists systems where a diagram greatly improves transmission, or may even be required, for example, in representing a data structure in a programming language such as Lisp \cite[67]{diagrams}, or a the representation of a dynamical system in physics. To try and describe an environment diagram in a computer science class without a blackboard would be more than difficult.


\begin{quotation}
[P]roblem solvers in domains like physics and engineering make extensive use of diagrams, a form of pictures, in problem solving, and many distinguished scientists and mathematicians (e.g., Einstein, Hadamard) have denied that they ``think in words'' \cite[2]{10000words}
\end{quotation}
If images and diagrams are so important for the transmission of information, then it should be an important focus for the creation of academic works and documentation. 


The Human Visual System