Pessoa et al. (1998a) summarize a wide body of data suggesting that perceptual filling-in phenomena can be attributed to neural filling-in processes. However, they reject, on philosophical grounds, the hypothesis that filled-in representations in the brain are the immediate substrate of visual percepts. It is proposed in this commentary that resonant binding between distributed cortical areas may instead be the crucial ingredient for conscious visual percepts, and that filling-in processes may facilitate the interactions between behaving organisms and object surfaces. These suggestions circumvent some of the philosophical problems associated with the idea of localized visual representations.

(1) The main issue with regard to modal and amodal completion is not which phenomena are cognitive, and which perceptual. At the level of the animal, both are visuo-cognitive. At the level of visual processing, however, we need to dissect the different functional effects of these kinds of completion. (2) Resonant binding between distributed cortical areas may play a role in perceptual completion, but evidence is needed.

Heyes's (1998) skepticism about theory of mind (ToM) in nonhuman primates exploits the idea of a strong and unified theory of mind in humans based on an unanalyzed category of mental state. It also exploits narrow debates about crucial observations and experiments while neglecting wider evolutionary trends. I argue against both exploitations.

The “somatic marker mechanism” (SMM; Damasio 1994) is proposed as the cognitive and neural basis of the theory of mind mechanism. The SMM evolved for evaluating the intentions, dispositions, and relationships of conspecifics; hence, it is adaptive in the social domain. It is predicted that chimpanzees will indeed have theory of mind (ToM) ability, but that this will be socially domain-specific. Domain-general ToM will be found only in primates with abstract, symbolic language (adult humans). Putative ToM tests require revision in the light of these distinctions.

Heyes's (1998) triangulation approach to distinguishing a “theory” of mind (ToM) from a “theory” of behavior (ToB) in chimpanzees fails. The ToB theorist can appeal to the explicit training sessions and analogical reasoning to explain/predict the chimpanzees' behaviors. An alternative triangulation experiment is sketched, demonstrating how the removal of such training sessions paves the way toward solving the distinguishability problem.

The commentators do not contest the target article's claim that there is no compelling evidence of theory of mind in primates, and recent empirical studies further support this view. If primates lack theory of mind, they may still have other behavior control mechanisms that are adaptive in complex social environments. The Somatic Marker Mechanism (SMM) is a candidate, but the SMM hypothesis postulates a much weaker effect of natural selection on social cognition than the theory of mind hypothesis (on inputs to cognitive mechanisms, not on the mechanisms themselves), and there is currently no evidence that it is specific to social stimuli or to primates. “Two Guesser” training would make the goggles test too chauvinistic, and in its current form the goggles problem could not be solved by physical matching because, while wearing goggles, an individual cannot see itself seeing.

Schyns et al.'s (1998) target article raises a conflict between the need for a fixed functional architecture in an explanatory cognitive science and the need for a system to learn to detect new features. This conflict can be resolved by avoiding the scope slip in which properties of objects are erroneously viewed as being properties of their representations.

Dawson's provocative comment makes three connected points: (1) to be falsifiable, theories that assume flexible features must constrain their feature creation and mechanisms, (2) the explanatory power of such functional theories is rooted in the properties of their underlying physical mechanisms, and (3) to derive the relevant constraints of feature creation from these mechanisms, it is critical to avoid the scope slip. We will argue here that even though we agree with (1) and (2), (3) confuses two different levels of analysis of computational systems: the functional identification and the physical implementation of relevant constraints.