Several philosophers consider the conscious phenomenal content and activity, such as William Lycan,[5] Alex Byrne[6] or Francois Tonneau;[7] Teed Rockwell[8] or Riccardo Manzotti.
The contents of some beliefs depend on how things are outside the subject" (Jackson and Pettit 1988, p. 381)[14] However, neither Dretske nor Lycan go far as to claim that the phenomenal mind extends literally and physically beyond the skin.
In sum they suggest that phenomenal contents could depend on phenomena external to the body, while their vehicles remains inside.
The mind then is no longer inside the skull, but it is extended to comprehend whatever tools are useful (ranging from notepad and pencils up to smartphones and USB memories).
While commenting on Andy Clark's last book Supersizing the Mind,[17] David Chalmers asks "what about the big question: extended consciousness?
[19] Enactivism builds upon the work of other scholars who could be considered as proto externalists; these include Gregory Bateson, James J. Gibson, Maurice Merleau-Ponty, Eleanor Rosch and many others.
For instance, Kevin O'Regan and Alva Noë suggested in a seminal paper that the mind is constituted by the sensory-motor contingency between the agent and the world.
In any case he is an externalist when he claims that "What perception is, however, is not a process in the brain, but a kind of skilful activity on the part of the animal as a whole.
The enactive view challenges neuroscience to devise new ways of understanding the neural basis of perception and consciousness" (Noë 2004,[20] p. 2).
Enactivism receives its share of negative comments, particularly from neuroscientists such as Christof Koch (Koch 2004,[22] p. 9): "While proponents of the enactive point of view rightly emphasize that perception usually takes place within the context of action, I have little patience for their neglect of the neural basis of perception.
Some externalists suggest explicitly that phenomenal content as well as the mental process are partially external to the body of the subject.
[23] Dwelling on John Dewey's heritage, he argues that the brain and the body bring into existence the mind as a "behavioral field" in the environment.
Another radical form of phenomenal externalism is the view called the spread mind by professor Riccardo Manzotti.
He explains that consciousness is both inside and outside the brain, and that the frontier that separates both realms is useless and a burden in the explanation of the self.
[citation needed] In his Anthropology of the Brain: Consciousness, Culture, and Free Will (Cambridge University Press, 2014; originally published in Spanish in 2005) he criticizes both externalism and internalism.