This commentary highlights the distinction between belief and pragmatic acceptance, and asks whether the positive illusions discussed in section 13 of the target article may be judicious pragmatic acceptances rather than adaptive misbeliefs. I discuss the characteristics of pragmatic acceptance and make suggestions about how to determine whether positive illusions are attitudes of this type.

Carruthers offers a promising model for how “we” know the propositional contents of “our” own minds. Unfortunately, in retaining talk of first-person access to mental states, his suggestions assume that a higher-order self is already “in the loop.” We invite Carruthers to eliminate the first-person from his model and to develop a more thoroughly third-person model of metacognition.

We agree that sexual selection is a more comprehensive explanation for sex differences in direct aggression than social role theory, which is an unparsimonious and vestigial remnant of human exceptionalism. Nevertheless, Archer misses several opportunities to put the theoretical predictions made by himself and by others into direct competition in a way that would further the interests of strong inference.

Del Giudice's model of sex-specific attachment patterns demonstrates the usefulness of infusing life history theory with principles of sexual selection. We believe a full synthesis between the two theories provides a foundation for a comprehensive model of alternative reproductive strategies. We extend Del Giudice's ideas based on our own program of research, focusing specifically on the importance of intrasexual competition and the individual phenotype during development.

Laughing, humor, and tickling, but not tearing and crying, involve the give-and-take that provides value and a basis for exchange in the psychosexual marketplace.

According to I3 Theory, individuals enact aggressive behaviors when (a) instigating triggers are severe, (b) impelling forces are strong, and/or (c) inhibiting forces are weak. Archer's analysis of human sex differences in aggression could be bolstered by a careful analysis of male-female discrepancies in reactivity (or exposure) to instigating triggers, proneness toward impelling forces, and/or proneness toward inhibiting forces.

Carruthers views unsymbolized thinking as “purely propositional” and, therefore, as a potential threat to his mindreading-is-prior position. I argue that unsymbolized thinking may involve (non-symbolic) sensory aspects; it is therefore not purely propositional, and therefore poses no threat to mindreading-is-prior. Furthermore, Descriptive Experience Sampling lends empirical support to the view that access to our own propositional attitudes is interpretative, not introspective.

Parent-infant emotional expressions vary according to parent and infant gender. Such parent-infant interactions critically affect infant development. Neuroimaging research is exploring emotion-related brain function that varies according to gender, and regulates parenting thoughts and behaviors in the early postpartum. Through specific brain functions, parenting serves to program the infant brain for the next generation of sex-specific emotional expression.

This commentary explores the reproductive strategies and attachment patterns among homeless youths. Del Giudice's integrated evolutionary model is applied to a homeless youth population that must function in ecological settings of constant high risk and stress. Different reproductive needs result in different patterns of high-risk behaviors. Intervention considering the sex differences, life history, and early caregiver–child relationships is suggested.

We propose another positive illusion – overconfidence in the generalisability of one's theory – that fits with McKay & Dennett's (M&D's) criteria for adaptive misbeliefs. This illusion is pervasive in adult reasoning but we focus on its prevalence in children's developing theories. It is a strongly held conviction arising from normal functioning of the doxastic system that confers adaptive advantage on the individual.

With respect to aggressiveness it is not enough to say that humans are “like other mammals.” We resemble only those species where males have higher maximum reproductive rates than females. In such species males evolve a set of hormonally mediated competitive traits via sexual selection. Because humans match the predictions of this general evolutionary model, attempts to (re)explain men's aggressiveness in sociological terms are superfluous and misleading.

The target article proposes a model to explain the emergence of sex differences in attachment in middle childhood and their implications for reproductive strategies. While biological factors are prominent in the model, little is said about the social context of middle childhood and its contributions. There is also a need to clarify the fundamental nature of attachment in middle childhood.

We argue that many evolved biases produced through selective forces described by error management theory are likely to entail misbeliefs. We illustrate our argument with the male sexual overperception bias. A misbelief could create motivational impetus for courtship, overcome the inhibiting effects of anxiety about rejection, and in some cases transform an initially sexually uninterested woman into an interested one.

The two-dimensional model of social relations outlined in the target article has striking convergence with empirically derived dimensional models of interpersonal perception, inter-group perception, and face evaluation. All these models posit two-dimensional structures related to perceptions of valence/affiliation and power/status. Although these models are parsimonious, they may be insufficient to account for behaviors in specific contexts.

Thinkers in related fields such as philosophy, psychology, and education define metacognition in a variety of different ways. Based on an emerging standard definition in psychology, we present evidence for metacognition in animals, and argue that mindreading and metacognition are largely orthogonal.

Evolutionary Life History Theory (LHT) is a powerful framework that can be used for understanding behavioral strategies as contingent adaptations to environmental conditions. Del Giudice uses LHT as a foundation for describing the attachment process as an evolved psychological system which evaluates life conditions and chooses reproductive strategies appropriate in the developmental environment, integrating findings across several literatures.

We present evidence that smiling is positively associated with positive affect in women and negatively associated with negative affect in men. In line with Vigil's model, we propose that, in women, smiling signals warmth (trustworthiness cues), which attracts fewer and more intimate relationships, whereas in men, smiling signals confidence and lack of self-doubt (capacity cues), which attracts numerous, less-intimate relationships.

While Carruthers denies that humans have introspective access to cognitive attitudes such as belief, he allows introspective access to perceptual and quasi-perceptual mental states. Yet, despite his own reservations, the basic architecture he describes for third-person mindreading can accommodate first-person mindreading without need to posit a distinct “introspective” mode of access to any of one's own mental states.

Human aggression has two important dimensions: within-group aggression and between-group aggression. Archer offers an excellent treatment of the former only. A full explanation of sex differences in aggression will fail without accounting for our history of inter-group aggression, which has deep evolutionary roots and specific psychological adaptations. The causes and consequences of inter-group aggression are dramatically different for males and females.

I take up the challenge of why false beliefs are better than “cautious action policies” (target article, sect. 9) in navigating adaptive problems with asymmetric errors. I then suggest that there are interactions between supernatural beliefs, self-deception, and positive illusions, rendering elements of all such misbeliefs adaptive. Finally, I argue that supernatural beliefs cannot be rejected as adaptive simply because recent experiments are inconclusive. The great costs of religion betray its even greater adaptive benefits – we just have not yet nailed down exactly what they are.