Philosophers have overall studied intentional actions that agents attempt to perform in the world. However the pioneers of the logic of action, Belnap and Perloff, and their followers have tended to neglect the intentionality proper to human action. My primary goal is to formulate here a more general logic of action where intentional actions are primary as in contemporary philosophy of mind. In my view, any action that an agent performs involuntarily could in principle be intentional. Moreover any involuntary action of an agent is an effect of intentional actions of that agent. However, not all unintended effects of intentional actions are the contents of unintentional actions, but only those that are historically contingent and that the agent could have attempted to perform. So many events which happen to us in our life are not really actions. My logic of action contains a theory of attempt, success and action generation. Human agents are or at least feel free to act. Moreover their actions are not determined. As Belnap pointed out, we need branching time and historic modalities in the logic of action in order to account for indeterminism and the freedom of action. Propositions with the same truth conditions are identified in standard logic. However they are not the contents of the same attitudes of human agents. I will exploit the resources of a non classical predicative propositional logic which analyzes adequately the contents of attitudes. In order to explicate the nature of intentional actions one must deal with the beliefs, desires and intentions of agents. According to the current logical analysis of propositional attitudes based on Hintikka's epistemic logic, human agents are either perfectly rational or completely irrational. I will criticize Hintikka's approach and present a general logic of all cognitive and volitive propositional attitudes that accounts for the imperfect but minimal rationality of human agents. I will consider subjective as well as objective possibilities and explicate formally possession and satisfaction conditions of propositional attitudes. Contrary to Belnap, I will take into account the intentionality of human agents and explicate success as well as satisfaction conditions of attempts and the various forms of action generation. This chapter is a contribution to the logic of practical reason. I will formulate at the end many fundamental laws of rationality in thought and action. I will only consider here individual actions and attitudes of single agents at one moment. Examples of such individual actions are intended body movements like voluntarily raising one's arm, some effects of these movements like touching something and saluting someone, mental actions like judgements and elementary illocutionary acts such as assertions and requests. Whoever performs an action at a moment has individual beliefs, desires and intentions at that very moment. Individual actions (and attitudes) of agents at a single moment are the simplest kinds of action (and attitudes) from a logical point of view. They part of other kinds of individual or collective actions (and attitudes) which last during several moments of time. In order to contribute to the foundations of the logic of action I will attempt to answer general philosophical questions: What is the logical form of proper intentional actions? Which attitudes do they contain? In my view, attempts are constitutive of intentional actions. Attempted actions have success conditions: either agents succeed or fail in performing them? How can we define success and failure? We need an account of agents' reasons in our logic of action and attitudes. Indeed agents have theoretical reasons for believing propositions and they make their attempts for practical reasons. Their intentional actions can both create reasons and be subject to demands for reasons i.e. for justifications. Moreover voluntary actions are related by the relation of being means to achieve ends (Aristotle). Agents make their attempts in order to perform other actions. How can we account for their objectives? Our intentional actions have involuntary effects in the world. In walking intentionally on the snow an agent might unintentionally slip and fall. What are the logical relations that exist between our intentional and unintentional actions? Some types of action strongly commit the agent to performing other types of action. Whoever shouts produces sounds. Any instance of an action of the first type contains an action of the second type. Moreover certain action tokens generate others in certain circumstances. Whoever expresses an attitude that he does not have, is lying. But he could be sincere at another moment. What are the basic laws governing agentive commitment and action generation? In particular, how can agents perform certain actions by way of performing others? Are all actions performed by an agent at a moment generated by a single basic intentional action of that agent at that moment? If yes, what is the nature of basic actions? As Brentano (1993) pointed out, agents of propositional attitudes and intentional actions have intentionality: they are directed at objects and facts of the world that they represent. From a logical point of view, propositional attitudes have logically related conditions of possession and of satisfaction. Whoever possesses a propositional attitude is in a certain mental state: he or she represents what has to happen in the world in order that his or her attitude is satisfied. Beliefs are satisfied whenever they are true, desires whenever they are realized and intentions whenever they are executed. So agents having beliefs represent how things are in the world according to them. Agents having desires represent how they would prefer things to be in the world and agents having intentions represent how they should act in order to execute their intentions. Propositional attitudes consist of a psychological mode M with a propositional content P. They are the simplest kinds of individual attitudes directed at facts. My first objective here is to explicate adequately possession and satisfaction conditions of all propositional attitudes. My second objective is to explicate the nature of intentional actions and the different kinds of action generation whether voluntary or not. According to standard epistemic logic human agents are either perfectly rational or totally irrational. I will advocate an intermediate position compatible with contemporary philosophy of mind according to which human agents are not perfectly but minimally rational. In my logical approach, one can formulate adequate laws of psychological commitment and avoid current epistemic and volitive paradoxes. In order to account for minimal rationality(1) I will exploit the resources of a non classical propositional predicative logic that distinguishes propositions with the same truth conditions that do not have the same cognitive or volitive value. The structure of this chapter is the following. I will explain in the first section my predicative analysis of propositional contents. Next I will explicate components of psychological modes and define possession and satisfaction conditions of propositional attitudes. I will explain in the third section the principles(2) of my logic of action where intentional actions are primary as in contemporary philosophy.(3) Because intentional actions are actions that agents attempt to perform in the world, the basic individual actions of each agent are in my logic his or her primary attempts (usually attempts of body movement). My ideographical object-language has richer expressive capacities than that of Belnap. It expresses in addition to modalities, time and individual actions of agents, their attempts and their cognitive and volitive propositional attitudes. I will give a formal account of intentionality and explicate the nature of attempts and forms of action generation in the fourth section.(4) In the last section I will enumerate a few valid laws of my logic after having criticized Searle's skepticism against the logic of practical reason. I will also explain why the logic of action is so important for the purposes of illocutionary logic.
