Where does modality collide?

In logic, modality is the classification of a proposition by its mode of truth: whether it is necessary, possible, contingent, or impossible, rather than simply true or false. It is formalised in modal logic by the operators box, for necessity, and diamond, for possibility, and given a semantics in which a sentence is evaluated across a set of possible worlds joined by an accessibility relation. Kripke's 1959 A completeness theorem in modal logic supplied a completeness proof for this possible-worlds treatment. The referent is a way a proposition can be true, not a count of peaks in a data set, a scanner in a clinic, or a channel of sensation.[1]

Unit

A proposition's mode of truth, as necessary, possible, or contingent

Recovery means

Not applicable

Measured by

Formalised with the operators box and diamond and evaluated across possible worlds joined by an accessibility relation

In statistics, the modality of a distribution is the number and arrangement of its modes, the peaks in its density: a distribution is unimodal with one peak, bimodal with two, or multimodal with several. It is a property of shape, distinct from central tendency and from spread, and a bimodal sample often signals a mixture of two underlying groups that a single mean would hide. Silverman's 1981 Using kernel density estimates to investigate multimodality and Hartigan and Hartigan's 1985 dip test gave formal ways to judge how many modes a sample supports. The referent is the peak structure of a distribution, not a mode of truth, an imaging device, or a sensory channel.[2][3]

Unit

The count and arrangement of peaks in a distribution

Recovery means

Not applicable

Measured by

Read from a density estimate or histogram, and tested formally by the dip statistic or by kernel density bandwidth methods

In perceptual psychology, a sensory modality is a channel of sensation defined by its receptors and neural pathway, such as vision, audition, touch, smell, or taste. A central question is how the brain combines signals across modalities, and this cross-modal or multimodal integration can sharpen a percept when the channels agree. Stein and Stanford's 2008 Multisensory integration reviewed how single neurons merge inputs from different sensory modalities, and Ernst and Banks's 2002 study showed vision and touch being combined in a statistically near-optimal way. The referent is a biological pathway of perception, not a mode of truth, a count of peaks, or a piece of clinical equipment.[4][5]

Unit

A channel of sensation, such as vision, audition, or touch

Recovery means

Not applicable

Measured by

Identified by its receptors and pathway, and studied by how signals from different channels combine in cross-modal integration