Let us define the concept of point of view related to a given pole of an A/Ā duality: we get then, for example (at the level of the extension/restriction duality) the standpoint by extension, as well as the viewpoint by restriction. Similarly, the qualitative viewpoint or perspective results from it, as well as the quantitative point of view, etc.. (at the level of the qualitative/quantitative duality). Thus, when considering a given object *o* (either a concrete or an abstract object such as a proposition or a reasoning), we may consider it in relation to various dualities, and at the level of the latter, relative to each of its two dual poles.

The underlying idea inherent to the viewpoint relative to a given duality, or to a given pole of a duality, is that each of the two poles of the same duality, all things being equal, deserve an equal legitimacy. In this sense, if we consider an object *o* in terms of a duality A/Ā, one should not favour one of the poles with respect to the other. To obtain an objective point of view with respect to a given duality A/Ā, one should place oneself in turn from the perspective of the pole A, and then from that of the pole Ā. For an approach that would only address the viewpoint of one of the two poles would prove to be partial and truncated. The fact of considering in turn the perspective of the two poles, in the study of an object *o* and of its associated reference class allows to avoid a subjective approach and to meet as much as possible the needs of objectivity.

Franceschi, P., “Une classe de concepts” (in english), *Semiotica*, vol. 139 (1-4), 2002, pages 211-226.

Ambiguous images ** ▣** Arbitrary focus

**Bistable perception**

**▣****Complementarity relationship**

**▣****Conflict resolution**

**▣****▣**Conflict resolution with matrices of concepts

**▣**Conflict types relating to matrices of concepts

**▣**Contrary relationship

**▣**Courage

**▣**Dialectical contextualism

**▣**Dialectical monism

**▣**Dialectical monism in Aztec philosophy

**▣**Dialectical monism in Heraclitus

**▣**Dichotomic analysis

**▣**Dichotomic analysis applied to paradox resolution

**▣**Dichotomous reasoning

**▣**Disqualification of one pole

**▣**Disqualification of the positive

**▣**Doctrine of the mean

**▣**Doomsday argument

**▣**Dualities

**▣**Dual poles

**▣**Extreme opposition

**▣**General cognitive distortions

**▣**Instance of one-sidedness bias

**▣**Liar paradox

**▣**Matrix of concepts

**▣**Maximization

**▣**Mental filter

**▣**Minimization

**▣**Bistable cognition

**▣**Omission of the neutral

**▣**One-sidedness bias

**▣**One-sided viewpoint

**▣**Opposition relationship

**▣**Principle of dialectical indifference

**▣**Requalification into the other pole

**▣**Reference class

**▣**Reference class problem

**▣**Reference class problem in philosophical paradoxes

**▣**Reference class problem in the Doomsday argument

**▣**Reference class problem in Hempel’s paradox

**▣**Reference class problem in the surprise examination paradox

**▣**Selective abstraction

**▣**Sorites paradox

**▣**Specific cognitive distortions

**▣**Surprise examination paradox

**▣**System of taxa

**▣**Two-sided viewpoint

**▣**Viewpoint of a duality

**▣**Viewpoint of a pole

(c) Paul Franceschi