Here is Thierry Aimar’s intro to his paper for Hayek in Mind.

Contemporary analysis usually divides games of chance into three dimensions. In Machina and Schmeidler’s (1992) terms, this division can be viewed based on the example of an urn containing 90 balls of different colors, out of which an agent pulls a ball, of which he must ex ante guess its color to achieve a predetermined gain. If the agent knows that the number of red, white, and black balls is the same (30), he finds himself in a situation of risk: He knows the possible consequences and the probability distributions, that is, he has one in three chances of getting a ball of any particular color. However, if he knows that these balls are red, white, and black, but in indefinite proportions, he is confronted with situations qualified as uncertainty: The consequences are known, but the probability distributions are not. Yet again, if the agent knows there are 90 balls of different colors in the urn but does not know how many of these colors there are, he is in a state of incomplete information: The agent is unable to define the list of possible outcomes (situation of ambiguity) and can expect some surprises identifiable ex ante, as states of nature are identifiable. An extra dimension may be added to this distinction: If the agent has himself placed 30 red balls in the box, but he does not know what other elements of indefinite character and number there are in the box, nor the structure of gains or losses associated with various results, then we can consider that the agent is in a position of ignorance. Not only is he unable to define the list of consequences of the game, but he also does not know the distribution of events. The agent is able to define what he knows, but unlike the three previous cases, he cannot determine the scope and nature of what he ignores. The surprise is necessarily unexpected in the sense that the agent is unable to identify ex ante the possible states of nature. It is in this latter perspective that Kirzner (1973, 1979, 1982) argues that market actors face a phenomenon of ‘‘genuine ignorance,’’ reflecting their inability to know all the opportunities for exchange or profit available in an economy. At any point in time, each individual perceives only fragmentary aspects of social reality in which he participates, and not its other facets. Each exchange is made in ignorance of other exchanges performed at the same time; thus, there is no common knowledge of prices and no actor can perceive the whole. In a monetary economy, the consequences of these independent exchanges are mutually dependent. The implications of this genuine ignorance on the coordination of activities are thus considerable. Using the example of Schmeidler and Machina’s urn (1992) from the time when the consequences of a draw for each individual depend on the (unknown) number of elements (of unknown character) deposited in the ballot box by an (unknown) number of (unknown) people, the ability of such a game to produce a balance is at least questionable. The stakes of this phenomenon of ignorance compel us to identify its sources. These are not found in any complexity of information, neither in the cost of its acquisition nor in its treatment (deliberation) from a perspective of bounded rationality. They come from a more fundamental phenomenon of dynamic subjectivism. According to authors such as Kinder (1973, 1979, 1997) and Lachmann (1977, 1986), agents’ preferences, endowments, knowledge, and strategies should be defined as personal, unique. Therefore, each individual is a priori ignorant of how others evaluate goods and services. Economic analysis is not therefore based on a perfect, or even sufficient knowledge of actors to coordinate their activities. The diversity of actors’ preferences, interpretations, and expectations would certainly not be a problem if they were constants. A process of trial and error would lead to new learning, opening onto a price structure that would allow coordination. But this is in fact not the case because the individual performances would change continuously, according to an endogenous process, ultimately explained by ignorance or internal self-ignorance (Aimar, 2008a). As Hayek (1951a, 1951b) explained, the actor can only partially perceive the existing opportunities for satisfaction, for reasons related to the organization of the human brain and the tacit characteristic of knowledge. His conscious choices being ignorant of a portion of his subjectivity, he makes mistakes, expressed by disappointment with satisfaction. He undergoes a de facto internal discoordination, forcing him to change his representations to make his beliefs conform to the reality of his interior environment. But changing choices results in transforming his internal environment and de facto creates new unknown areas. The mind, constantly evading the consciousness’s desire to fully absorb it, makes the process of self-discovery never-ending. Thus, market discoordination, the result of genuine ignorance, is finally but an internal discoordination, consequence of a phenomenon of self-ignorance. It was around this phenomenon of genuine ignorance and its perverse effects on coordination between individuals that Kirzner introduced the theme of entrepreneurship. The entrepreneurial function, driven by the incentive of profit, is to discover unperceived opportunities. Mobilizing qualities of alertness, reflected in cognitive openness, it reveals previously hidden information. Through his discoveries being translated into new money transactions, the entrepreneur socializes his knowledge and contributes to pulling market activities toward coordination. He goes beyond reducing ignorance; he transforms ignorance into uncertainty. But according to Kirzner, a parallel mission of the entrepreneur is to organize already discovered opportunities in the form of firms’ production plans, in order to protect them from risk of obsolescence resulting from the volatility of data. In a dynamic world, discovery and exploitation of opportunity are then the two faces of entrepreneurship. The author argues that these two dimensions may be contradictory in the entrepreneurial mind. As much as discovery implies a cognitive opening to the outside, all exploitation of discovered opportunities is accompanied by elements of mental rigidity. These take the form of cognitive closure, thus opposing the entrepreneur’s perception of new opportunities. The aim of this contribution is to illuminate by the structure of this contradiction by economic analysis, to provide the means to verify it through experimental economics and to consider its extensions in terms of neuroeconomics. Our plan is this: After explaining the basics of the theory of entrepreneurship and the elements that determine its duality, we will define the bases for an experimental protocol likely to support our thesis of an opposition in the cognitive field between the relative strengths of discovery and the exploitation of opportunities in the entrepreneurial mind. The last section forms the conclusion.