Conventional measures of mental ability, such as intelligence tests and scholarship, show some of the very highest records belong to INFP and INFJ types, who relegate thinking to last place or next to last. The preference for thinking appears to have far less intellectual effect than the preference for intuition, even in some technical fields, such as scientific research, where its influence was expected to be most important.

Extraverts ... cannot understand life until they have lived it. Introverts ... cannot live life until they understand it.

What children need is the conviction that satisfaction can and must be earned. ... Spoiled children do not learn the must.

Although intelligence tests are usually speed tests for the sake of convenience, it is debatable whether speed has any rightful place in the basic concept of intelligence.

Introverted feeling types have a wealth of warmth and enthusiasm, but they may not show it until they know someone well. They wear their warm side inside, like a fur-lined coat.

[On Jung's theory of psychological types:] My mother, Katharine C. Briggs, introduced it into our family and made it a part of our lives. She and I waited a long time for someone to devise an instrument that would reflect not only one's preference for extraversion or introversion but one's preferred kind of perception and judgment as well. In the summer of 1942 we undertook to do it ourselves.

Conventional measures of mental ability, such as intelligence tests and scholarship, show some of the very highest records belong to INFP and INFJ types, who relegate thinking to last place or next to last. The preference for thinking appears to have far less intellectual effect than the preference for intuition, even in some technical fields, such as scientific research, where its influence was expected to be most important.