The text discusses how an artist must be able to convey thoughts through skill and concentration. It uses walking and running as metaphors for human will and muscular actions. The artist should carefully avoid depicting animals with human emotions or actions.
Muscle and Their Service.
The artist aims to reveal the thoughts of himself and his sculptures to the observer. Each should accomplish this through his own diligence and concentration, achieving things that seem impossible by the mere act of creation.
An example may clarify the previous statement: It should be noted that, although common walking and running depend on both will and the human body's reaction, we often move without conscious thought of our feet and legs, while the muscles must respond to commands from the mind to carry out motion naturally.
In a swiftly moving image, such as with a runner, we should see the tension of muscles in the face and the efforts of arms and hands more clearly highlighted, all these expressions in runners and warriors appearing intense and natural.
Just as the likelihood of thought and intellectual actions are given solely to humans among creatures, so the artist must carefully ensure that no act or passion is depicted in beasts as they should not display human emotions.
Translation Notes:
Mensfch: Refers to 'human' or 'man'; distinguished from beasts.
Beeld: Refers to 'image' or 'sculpture'.