Where does temperament collide?

In developmental psychology, temperament is the set of early-appearing, biologically based individual differences in how a person reacts to the world and regulates that reaction: differences in emotional reactivity, activity, attention, and self-control that show up in infancy and stay fairly stable. Thomas and Chess, in the New York Longitudinal Study reported in Temperament and Development, grouped babies into easy, difficult, and slow-to-warm-up patterns from ratings of qualities like rhythmicity, approach, and mood. Kagan, Reznick, and Snidman's work on behavioral inhibition traced how toddlers who were restrained and wary with unfamiliar people stayed that way years later, and linked the pattern to physiological reactivity. The referent is a measurable style of reacting and regulating in a living child, not a way of tuning a scale, a way of heat-treating steel, or an ancient theory of bodily fluids.[1][2]

Unit

An early-appearing style of reactivity and self-regulation, rated across situations

Recovery means

The self-regulation side of temperament lets a child damp down an initial reaction over time, and that capacity itself grows with development

Measured by

Assessed by caregiver-report questionnaires, by structured observation of a child's response to novelty, and by physiological indices such as heart rate and cortisol

In music, a temperament is a system for tuning an instrument that decides how the octave is divided into notes and which intervals are made slightly impure so that the whole set works together. Pure or just intonation tunes intervals to simple frequency ratios, but those ratios do not close neatly into a repeating scale, so a temperament spreads the leftover mismatch around. Meantone temperament keeps most thirds sweet at the cost of some other intervals, while equal temperament divides the octave into twelve identical steps so every key sounds the same and none is perfectly pure. Barbour's Tuning and Temperament: A Historical Survey traces these schemes and the compromises each one makes. The referent is a rule for compromising intervals in a scale, measured in cents, and it has nothing to do with a child's disposition, a heat treatment, or the humours.[3]

Unit

A scheme for dividing the octave and adjusting intervals, in cents

Recovery means

Not applicable

Measured by

Described by the size in cents of each interval, compared against the pure whole-number ratios it departs from

In the history of medicine, the temperaments are the four character types of ancient and medieval humoral theory: sanguine, choleric, melancholic, and phlegmatic. The theory, rooted in the Hippocratic writings and systematised by Galen, held that health and disposition depended on the balance of four bodily humours, blood, yellow bile, black bile, and phlegm, and that a person's ruling humour set their lasting temperament. This was a typology of personality tied to a physiology that later science discarded. Stelmack and Stalikas's Galen and the humour theory of temperament reconstructs the classical scheme and how it framed character. The referent is an ancient explanatory framework for personality and complexion, not a modern measured disposition, a tuning rule, or a heat treatment.[4]

Unit

A character type keyed to a supposedly dominant bodily humour

Recovery means

Not applicable

Measured by

Not measured in any modern way; inferred in the classical texts from a person's character, appearance, and complexion