A hallmark of intentional phenomena is what might be called ‘discontinuity,’ the idea that the intentional somehow stands outside the contingent natural order, that it possesses some as-yet-occult ‘orthogonal efficacy.’ Here’s how some prominent intentionalists characterize it:

“Scholars who study intentional phenomena generally tend to consider them as processes and relationships that can be characterized irrespective of any physical objects, material changes, or motive forces. But this is exactly what poses a fundamental problem for the natural sciences. Scientific explanation requires that in order to have causal consequences, something must be susceptible of being involved in material and energetic interactions with other physical objects and forces.” Terrence Deacon, Incomplete Nature, 28

“Exactly how are consciousness and subjective experience related to brain and body? It is one thing to be able to establish correlations between consciousness and brain activity; it is another thing to have an account that explains exactly…