Justification not yet generated — showing supporting facts

• Physicalists, including Smart (1959), Hill (1991), Block and Stalnaker (1999), McLaughlin (2001), and Melnyk (2003), argue that the best explanation for mind-brain supervenience is that conscious states are constituted by the brain states they supervene on.
• In overdetermination dualism, physical behavior is caused by both a conscious state and a brain state, where each cause is sufficient on its own to produce the effect.
• David Chalmers suggests that just as Newton's theory of gravitation explains why an apple falls by invoking a fundamental force rather than just correlating drop heights and times, a theory of consciousness should explain why brain states produce conscious states by invoking fundamental laws.
• Russellian monism posits that conscious states are the intrinsic nature of brain states, which implies that the causal actions of brain states and conscious states are identical.
• Brain scanning techniques such as PET and fMRI have revealed detailed correlations between specific conscious states and brain states, such as the correlation between seeing red and activity in the visual cortex, or anxiety and an overactive amygdala.
• C.D. Broad and Frank Jackson argued that conscious states could evolve as by-products of useful brain states, even if those conscious states themselves are inert.
• Russellian monism attempts to avoid the problems of dualism and physicalism by suggesting that conscious states are the intrinsic nature of brain states, meaning the causal action of brain states and conscious states are the same.
• Physicalism is supported by the observation that conscious states depend entirely on brain states, as indicated by neuroscience.
• Subjective idealism explains mind-brain correlations by regarding brain states as perceptions of one subject (a person observing someone else's brain) and conscious states as the perceptions or other conscious states of another subject (the person whose brain is being observed).
• Joseph Levine disputes that conscious states are reducible to neuronal or brain states, arguing that the bridges between conscious states and physical states are contingent rather than necessary.