PHILOSOPHY OF MIND A mental item is given its intentionality by an act of meaning (Meinen) There are two kinds of meaning: one kind is that which gives significance to a word, and the other kind is that which gives sense to a proposition ‘Each meaning is either a nominal meaning or a propositional meaning, or, still more precisely, either the meaning of a complete sentence or a possible part of such a meaning’ (LI vi 1) Every mental act will be an act of a certain kind, belonging to a particular species, which will be determined by its matter Every thought of a horse, whoever’s thought it is, belongs to the same species; and the concept horse is precisely the species to which all these thoughts belong Similarly, whenever anyone makes the judgement that blood is thicker than water, the meaning of that judgement, the proposition blood is thicker than water, is precisely the species to which all such acts of judgement belong If A agrees with the judgement of B, then while A’s judgement and B’s judgement are distinct individual mental events, they are, because they have the same matter, instances of the same species In his later writing Husserl called the individual act the noesis and the specific content the noema In addition to having matter, acts have qualities It is not only words and sentences that have meaning, and not only the corresponding mental acts and states, such as knowing and believing So too perception, imagination, emotion, and volition My seeing Rome and my imagining Rome are acts that have the same matter, or intentional object, but because seeing is different from imagining, they are acts of different quality (LI vi 22) Husserl’s theory of intentionality was a fertile one, and his account of it contains many shrewd observations and valuable distinctions But the nature of the act of meaning, which underpins the universe of mental phenomena, remains deeply mysterious In the 1920s and 1930s some philosophers attempted to present a philosophy of mind that would dispense altogether with intentionality Bertrand Russell, in his Analysis of Mind, presented an account of desire that made it definable in terms of the events that brought it to an end ‘A mental occurrence of any kind— sensation, image, belief or emotion,’ he wrote, may be a cause of a series of actions continuing, unless interrupted, until some more or less definite state of affairs is realized Such a series of actions we call a ‘behaviour cycle’ The property of causing such a cycle of occurrences is called ‘discomfort’ the cycle ends in a condition of quiescence, or of such action as tends to preserve the status quo The state of affairs in which this condition of 211