Where does inclination collide?

The angle between the plane of an orbit and a chosen reference plane, such as the ecliptic or a planet's equator, giving the tilt of the orbital path in space. Copernicus (1543), in De revolutionibus orbium coelestium, gave the tilts of the planetary orbits relative to the ecliptic, and Murray and Dermott (1999) set out the modern treatment in which inclination is one of the standard elements that fix an orbit, measured in degrees from zero for a coplanar orbit up to ninety for a polar one and beyond. The referent is a geometric angle between two planes in celestial mechanics, and it has nothing to do with a rock layer's tilt in the ground or a person's desire pulling against duty.[1][2]

Unit

One angle in degrees between an orbital plane and a reference plane

Recovery means

Not applicable

Measured by

Derived from tracked positions by fitting the orbit and reading the tilt of its plane against a reference such as the ecliptic

The angle that a bedding plane, fault, or other rock surface makes with the horizontal, called the dip, measured downward from level. Steno (1669), in De solido intra solidum naturaliter contento, argued that layers of rock are laid down flat and can later be tilted, so their present inclination records deformation, and modern structural geology (Fossen, 2010) defines the dip as the steepest angle the surface makes with the horizontal, from zero for a flat bed to ninety for a vertical one. The referent is the attitude of a rock surface in the ground, not the tilt of an orbit's plane in space or an inner pull toward desire.[3][4]

Unit

One angle in degrees between a rock surface and the horizontal

Recovery means

Not applicable

Measured by

Read in the field with a clinometer or compass-clinometer on an exposed rock surface, and mapped as dip and dip direction

In Kant's moral philosophy an inclination (Neigung) is a habitual desire rooted in feeling, a pull toward what one finds agreeable that can move the will apart from reason. Kant (1785), in the Groundwork of the Metaphysics of Morals, contrasts acting from inclination with acting from duty and holds that an action has moral worth only when it is done from duty rather than from an agreeable inclination, even where the two happen to coincide. The referent is a motive within a person, a desire set against moral obligation, and it is unrelated to the tilt of an orbit or the dip of a rock layer.[5]

Unit

One standing desire or propensity that moves the will

Recovery means

Not applicable

Measured by

Not measured numerically; identified by philosophical analysis of the motive behind an action