Albert Paul Weiss (September 15, 1879 – April 3, 1931) was a German American behavioral psychologist, theorist, scientist, and experimentalist.

His family moved to the United States shortly after his birth and lived in St. Louis, MO.

Weiss initially planned on majoring in physics, mathematics, and philosophy until he was inspired by his professor Max Meyer to become a psychologist.

As a scientist, Weiss emphasized the importance of applying scientific methods to studying non-physical concepts.

[2] His method of studying human behavior was considered to be overzealous and radical in comparison to traditional behaviorists.

This is why he believed the study of human behavior needed to be done in a carefully constructed scientific manner.

[1] Weiss believed the current psychological methodology of his time unfitting to study behaviorism because the main focus was physical and mental phenomena instead of the biological and social aspects that he thought were more important.

[1] His unparalleled attention to detail in his behavior studies is one of the main reasons why people today regard him as a radical behaviorist.

Specifically, he thought that human behavior and achievement could be combined to create one physical element.

Since Weiss was a materialist, he wanted to prove that language, a non-tactile thing, does have material origins.

He sought to use his materialist and monist views to explain questions regarding the mind that were still being debated.

[4] Weiss believed defining consciousness as experience was lacking because there was no way to expand upon this definition.

He also published Psychological Monograph, which discussed his work in acoustics and included the patents of his sound apparatus.

One of the most unusual works that Weiss wrote was Psychological Principles of Automotive Driving, based on his studies done on human-machine relationships.