Intentionality - The Modern Overview

The Modern Overview

The concept of intentionality was reintroduced in 19th-century contemporary philosophy by the philosopher and psychologist Franz Brentano in his work Psychology from an Empirical Standpoint (1874). Brentano described intentionality as a characteristic of all acts of consciousness, "psychical" or "mental" phenomena, by which it could be set apart from "physical" or "natural" phenomena.

Brentano coined the expression "intentional inexistence" to indicate the peculiar ontological status of the contents of mental phenomena. According to some interpreters the "in-" of "in-existence" is to be read as locative, i.e. as indicating that "an intended object exists in or has in-existence, existing not externally but in the psychological state" (Jacquette 2004, p. 102), while others are more cautious, affirming that: "It is not clear whether in 1874 this was intended to carry any ontological commitment" (Chrudzimski and Smith 2004, p. 205).

A major problem within intentionality discourse is that participants often fail to make explicit whether or not they use the term to imply concepts such as agency or desire, i.e. whether it involves teleology. Dennett (see below) explicitly invokes teleological concepts in the "intentional stance". However, most philosophers use intentionality to mean something with no teleological import. Thus, a thought of a chair can be about a chair without any implication of an intention or even a belief relating to the chair. For philosophers of language, intentionality is largely an issue of how symbols can have meaning. This lack of clarity may underpin some of the differences of view indicated below.

To bear out further the diversity of sentiment evoked from the notion of intentionality, Husserl followed on Brentano, and gave intentionality more widespread attention, both in continental and analytic philosophy. In contrast to Brentano's view, French philosopher Jean-Paul Sartre (Being and Nothingness) identified intentionality with consciousness, stating that the two were indistinguishable. German philosopher Martin Heidegger (Being and Time), defined intentionality as "care" (Sorge), a sentient condition where an individual's existentiality, facticity, and forfeiture to the world identifies their ontological significance, in contrast to that which is the mere ontic (thinghood).

Other 20th-century philosophers such as Gilbert Ryle and A.J. Ayer were critical of Husserl's concept of intentionality and his many layers of consciousness, Ryle insisting that perceiving is not a process and Ayer that describing one's knowledge is not to describe mental processes. The effect of these positions is that consciousness is so fully intentional that the mental act has been emptied of all content and the idea of pure consciousness is that it is nothing (Sartre also referred to "consciousness" as "nothing").

Platonist Roderick Chisholm has revived the Brentano thesis through linguistic analysis, distinguishing two parts to Brentano's concept, the ontological aspect and the psychological aspect. Chisholm's writings have attempted to summarize the suitable and unsuitable criteria of the concept since the Scholastics, arriving at a criterion of intentionality identified by the two aspects of Brentano's thesis and defined by the logical properties that distinguish language describing psychological phenomena from language describing non-psychological phenomena. Chisholm's criteria for the intentional use of sentences are: existence independence, truth-value indifference, and referential opacity.

In current artificial intelligence and philosophy of mind intentionality is a controversial subject and sometimes claimed to be something that a machine will never achieve. John Searle argued for this position with the Chinese room thought experiment, according to which no syntactic operations that occurred in a computer would provide it with semantic content.