I very much enjoyed Harro's comments below on the historical novelty of Brentano's
invention of intentionality and its absence in Victorian thought. (Strictly speaking:
Brentano revived a scholastic term, see below.)
  
  But I am, however, afraid that there is also a potential source of confusion in his
claim. What follows is in large part copied and pasted from the online article, by Pierre
Jacob,"Intentionality", The Stanford Encyclopedia of Philosophy (Fall 2003 Edition),
Edward N. Zalta (ed.), URL =
http://plato.stanford.edu/archives/fall2003/entries/intentionality/. This article is a
very useful resource in understanding the history and content of my claims below.
     
  The philosophic meaning of the word "intentionality" (as coined by Brentano) should not
be confused with the ordinary meaning of the word "intention."
  I quote Brentano:  
  Every mental phenomenon is characterized by what the Scholastics of the Middle Ages
called the intentional (or mental) inexistence of an object, and what we might call,
though not wholly unambiguously, reference to a content, direction toward an object (which
is not to be understood here as meaning a thing), or immanent objectivity. Every mental
phenomenon includes something as object within itself, although they do not do so in the
same way. In presentation, something is presented, in judgment something is affirmed or
denied, in love loved, in hate hated, in desire desired and so on.   This intentional
inexistence is characteristic exclusively of mental phenomena. No physical phenomenon
exhibits anything like it. We can, therefore, define mental phenomena by saying that they
are those phenomena which contain an object intentionally within themselves.
  I have included the first (otherwise very puzzling) sentence to make the historical
point about the Scholastics. As Jacob comments, "In the two paragraphs quoted above,
Brentano sketches an entire research programme based on three distinct theses. According
to the first thesis, it is constitutive of the phenomenon of intentionality, as it is
exhibited by mental states such as loving, hating, desiring, believing, judging,
perceiving, hoping and many others, that these mental states are directed towards things
different from themselves. According to the second thesis, it is characteristic of the
objects towards which the mind is directed by virtue of intentionality that they have the
property which Brentano calls intentional inexistence. According to the third thesis,
intentionality is the mark of the mental: all and only mental states exhibit
intentionality."
     
  So, when philosophers generally talk about (Brentano's) 'intentionality' it is not about
the goal-directedness of behavior/action (ordinary usage), but rather about the about-
ness/directness of thought (or the content(s) of thought). Brentano's intentionality can
become important in thinking about rationality of behavior, but only indirectly (when we
wonder how intentional objects, which are relational (this follows from their aboutness),
can be "causes'' or "reasons"). However, there is indeed a (mostly seperate) literature on
the question to what degree collective agency/rationality is possible in which
intentionality is often used in its ordinary sense distinct from Brentano's use. (The
literature is not entirely distinct because Searle has contribituted to both.)
     
  Yours,  
Eric Schliesser