Khaled Al-Sayer's Key Ideas from Please Understand Me II
by David Keirsey

Temperament is a configuration of inclinations, while character is a configuration of habits. Character is disposition, temperament pre-disposition.

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Put another way, our brain is a sort of computer which has temperament for its hardware and character for its software.

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Thus temperament is the inborn form of human nature; character, the emergent form, which develops through the interaction of temperament and environment.

Clearly, what sets human beings apart from the other animals are two advantages we have over them — words and tools. And what sets us apart from each other is the way we use words and tools. The great majority of us are predominantly concrete in our word usage, the rest predominantly abstract. And about half of us are utilitarian in our choice and use of tools, the other half cooperative.