Table 3.

Biconditional mental causality models, and their implications for comparative cognition

Assume p exists			The reality: p is indeterminable
p	q	p ⇔ q	p	q	p ⇔ q
Biconditional (p is a necessary cause for q; q if and only if p)
T	T	T	T?	T	?
T	F	F*	T?	F	?
F	T	F*	F?	T	?
F	F	T	F?	F	?

Under the assumption, at left, that p is determinable (i.e., that the presence and absence of p is determinable, hence a truth value can be legitimately applied to both p and q), the asterisks denote the states of the world that would disconfirm the premise p ⇔ q. The premise p ⇔ q would be falsified whenever p and q have incommensurate truth values (i.e., whenever one is true, or present, and the other is false, or absent). Here we argue that, in reality, because p is imaginary and cannot be objectively measured, as shown at right, therefore there is no possibility of disconfirming the premise p ⇔ q. Thus, all mental causality models that posit a certain mental state (p) to be a necessary cause for a particular behavior (q) are unfalsifiable