Methods in experimental economics are reminiscent of the methods employed by behaviorists in the first half of the twentieth century. Empirical and conceptual progress led the field of psychology away from the principles of behaviorism, and experimental economists should consider whether the criticisms leveled against behaviorists might apply equally to them.

Hertwig and Ortmann have made a laudable effort to bring together experimental practices in economics and in psychology. Unfortunately, they ignore one of the primary objectives of psychological research, which is an analytic description of general cognitive processes. Among experimental practices in probability judgment tasks they discussed, we will focus hereafter on enactment of scripts and repetition of trials.

The authors wish that the psychology of human decision making should borrow methodological rigor from economics. However, unless economics also borrows from psychology this poses a danger of overly limiting the phenomena studied. In fact, an expanded economic theory should be sought that is based in psychology (and ultimately neuroscience) and encompasses both rational and irrational aspects of decision making.

Hertwig and Ortmann suggest greater standardization of procedures in experimental psychology to help with problems of replicability and consistency of findings. It is argued that, (a) this view is inconsistent with their other interesting proposals, and (b) heterogeneity of method is appropriate in psychology.

The target article suggests that many practices of experimental economists are preferable to those used by psychologists studying judgment and decision making. The advantages of the psychological approach become clear when the focus of research shifts from choice output to choice processes. I illustrate this point with an example from research on similarity comparisons.

For a variety of reasons, including the common use of deception in psychology experiments, participants often disbelieve experimenters' assertions about important task parameters. This can lead researchers to conclude incorrectly that participants are behaving non- normatively. The problem can be overcome by deriving and testing normative models that do not assume full belief in key task parameters. A real experimental example is discussed.

Psychologists' lack of methodological uniformity reflects their greater breadth of enquiry than experimental economists. The need for a theoretical understanding of one-shot decisions validates research undertaken without the repetition of trials. Theories tested only with financial incentives may not reliably predict some classes of decision such as those involving health. Undue emphasis on the importance of replication risks the proliferation of theories with limited generalizability.

Hertwig and Ortmann imply that failure of many behavioral psychologists to observe several central methodological principles of experimental economics derives mainly from differences in disciplinary culture. I suggest that there are deeper philosophical causes, based (ironically) on a legacy of methodological individualism in psychology from which economists have substantially cured themselves through use of game theory. Psychologists often misidentify their objects of study by trying to wrench subjects out of their normal behavioral contexts in games.

Standard practices in experimental economics arise for different reasons. The “no deception” rule comes from a cost-benefit tradeoff; other practices have to do with the uses to which economists put experiments. Because experiments are part of scientific conversations that mostly go on within disciplines, differences in standard practices between disciplines are likely to persist.

The rhetoric of hypothesis testing implies that game theory is not testable if a negative result is blamed on any auxiliary hypothesis such as “rewards are inadequate.” This is because either the theory is not falsifiable (since a larger payoff can be imagined, one can always conclude that payoffs were inadequate) or it has no predictive content (the appropriate payoff cannot be prespecified).

My main argument is that the advice offered to experimental psychologists by Hertwig & Ortmann overlooks fundamental differences between the goals of researchers in psychology and economics. Furthermore, it is argued that the reduction of data variability is not always an end to be sought by psychologists. Variability that originates in individual differences constitutes valuable data for psychological research.

The adoption of experimental methods from economics, in particular script-enactment, performance-related payment, and the absence of deception, will turn experimental social psychology into a trivial science subject. Such procedures force participants to conform to a normative expectation that they must behave rationally and in accordance with their self-interest. The self-fulfilling prophecy inherent in these procedures makes it more difficult to conduct innovative social-psychological research.

Three comments take issue with specifics of the target article. First, I argue for the development of meta-theory to deal with inconsistencies in experimental results. Second, I advocate the use of the compatibility between experiment and application to decide on the optimal design and procedure of experimental studies. Last, I support the explicit incorporation of motivation into models of decision making.

Despite claims of pure pragmatism, Hertwig and Ortmann's negative perspective on deception suggests a selfish psychologist willing to sacrifice the reputation of the discipline in order to expedite the research. Although questions that appear to have correct answers may be investigated with complete openness, research that delves into personal secrets often requires deception as a tool to counter self-presentation bias.

Hertwig and Ortmann (H&O) rightly criticize the usage of deception. However, stationary replication may often have no ecological validity. Many economic experiments are not interactive; when they are, there is not much specifically validating H&O's psychological views on script enactment. Incentives in specific market structures may scaffold even zero rational decision-making, but this says very little about individual psychology.

This response reinforces the major themes of our target article. The impact of key methodological variables should not be taken for granted. Rather, we suggest grounding experimental practices in empirical evidence. If no evidence is available, decisions about design and implementation ought to be subjected to systematic experimentation. In other words, we argue against empirically blind conventions and against methodological choices based on beliefs, habits, or rituals. Our approach will neither inhibit methodological diversity nor constrain experimental creativity. More likely, it will promote both goals.

Category-specific impairments of object recognition and naming are among the most intriguing disorders in neuropsychology, affecting the retrieval of knowledge about either living or nonliving things. They can give us insight into the nature of our representations of objects: Have we evolved different neural systems for recognizing different categories of object? What kinds of knowledge are important for recognizing particular objects? How does visual similarity within a category influence object recognition and representation? What is the nature of our semantic knowledge about different objects? We review the evidence on category-specific impairments, arguing that deficits even for one class of object (e.g., living things) cannot be accounted for in terms of a single information processing disorder across all patients; problems arise at contrasting loci in different patients. The same apparent pattern of impairment can be produced by damage to different loci. According to a new processing framework for object recognition and naming, the hierarchical interactive theory (HIT), we have a hierarchy of highly interactive stored representations. HIT explains the variety of patients in terms of (1) lesions at different levels of processing and (2) different forms of stored knowledge used both for particular tasks and for particular categories of object.

Although the principles defining HIT find support within a variety of fields, the framework is currently underspecified in several respects, which prevents it from fully achieving its purpose. We highlight a number of such shortcomings and propose avenues for a resolution of some of these issues.

Developmental research on infants' categorization of living and nonliving objects finds that very young children are equally skilled in grouping such objects. The lack of a specialization for one type of object over another may be due to knowledge of function and the time frame for acquiring such knowledge.

HIT produces category-specific deficits without category- specific mechanisms by assuming that differences in properties of objects are transparently converted into differences in representational format. A complete model would specify the mechanisms that accomplish this. Such category-specific mechanisms may have evolved because assumptions about the properties of some kinds of objects (e.g., living things) are invalid for others (e.g., artifacts).