In exploring existing definitions of utopia we can consider three different aspects: content, form and function. Firstly, there is content. There is a common assumption that utopia should be a portrayal of the good society. It is however obvious that this will vary, being a matter not just of personal taste, but of the issues which appear to be important to different social groups, either in the same society or in different historical circumstances. […] The variation in content, however, makes it particularly difficult to use this as part of the definition of utopia. Definitions in terms of content tend to be evaluative and normative, specifying what the good society would be, rather than reflecting on how it may be differently perceived. The issue of possibility also relates directly to the content of a utopia, and again judgements differ. Secondly, one can attempt to define utopia descriptively, in terms of form. The common sense equation of utopia with a description of a good society (leaving aside the question of possibility) is one version of such a definition. Another is the equation of utopia with an ideal commonwealth. Some commentators take the form of More’s Utopia as a model and argue that utopia is a literary genre, involving the fictional depiction of an alternative society in some detail. However, as we have already suggested, depictions of the good society do not necessarily take the form of literary fictions – and indeed this form is only available under certain very specific historical conditions; is it then to be assumed that when these conditions do not exist, there are no utopias? Broader historical comparisons require more inclusive definitions, to accommodate changes in the way in which aspirations for a better life may be expressed. Thirdly, one may define utopia in terms of its function. This is less obvious; to focus on the function of utopia is already to move away from colloquial usage, which says nothing about what utopia is for, but implies that it is useless. […] utopia is seen as presenting some kind of goal, even if commentators as opposed to the authors of utopias do not see them as necessarily realisable in all their details. At the very least, utopias raise questions about what the goal should be. Many commentators, however, go further and use the function of utopia as a defining characteristic – although that function is differently represented by different authors. […] Broadly, one may divide approaches to utopian studies into two streams. The liberal-humanist tradition tends to focus on definitions in terms of form. In contrast a largely, but not exclusively, Marxist tradition has defined utopia in terms of its function – either a negative function of preventing social change or a positive function of facilitating it, either directly or through the process of the ‘education of desire’. Contemporary utopian studies draws on both these traditions, and definitions of both kinds may be found, although those in terms of form tend to predominate. […] It is argued that all definitions in terms of form, function or content are problematic. Not only do they place limits upon what may properly be regarded as utopian and thus upon the field of enquiry itself, they also obscure variations in the utopian genre. In order to make such a claim, one must of course be able to locate something which remains constant while content, form and function vary. This element, I would argue, is that of desire – desire for a better way of being and living. Levitas, The Concept of Utopia, p.5-8

Both the colloquial definitions and the anti-utopian position illustrate the fact that the concept itself is an ideological battleground. The elision between perfection and impossibility can serve to invalidate all attempts at change, reinforcing the claim that there is no alternative, and sustaining the status quo. Perhaps, as Khayyám suggests, we would do better to forget the future and drown our sorrows. But even among different groups committed to change, the derogatory meaning attaching to utopia is what dominates. People rarely claim that their own aspirations are utopian but even dream- ers may hurl the epithet at others. The rejection of other people’s projects as utopian and unrealistic is part of the process of promoting the merits of one’s own plans, and is thus an intrinsic part of the political process. Levitas, The Concept of Utopia, p.4

Colloquial usage thus tends to dismiss speculation about the good society as intrinsically impractical. This dismissal may be tolerantly good-humoured, seeing utopia as an interesting if esoteric byway of culture and the utopian as a well-meaning dreamer. It may, on the other hand, be extremely hostile, seeing attempts at instituting utopia as highly dangerous and leading to totalitarianism. This anti-utopian position is typified by Karl Popper and Friedrich Hayek. Levitas, The Concept of Utopia, p.3

Sometimes utopia embodies more than an image of what the good life would be and becomes a claim about what it could and should be: the wish that things might be otherwise becomes a conviction that it does not have to be like this. Utopia is then not just a dream to be enjoyed, but a vision to be pursued. Yet the very term utopia suggests to most people that this dream of the good life is an impossible dream – an escapist fantasy, at best a pleasant but pointless entertainment. Those utopians who seek to make their dreams come true are deemed to be hopelessly unrealistic, or worse, actively dangerous. The view that utopia is not escapist nonsense but a significant part of human culture is a fundamental assumption of the expanding field of utopian studies. Levitas, The Concept of Utopia, p.1

Utopia is the expression of the desire for a better way of being. This includes both the objective, institutional approach to utopia, and the subjective, experiential concern of disalienation. It allows for this desire to be realistic or unrealistic. It allows for the form, function and content to change over time. And it reminds us that, whatever we think of particular utopias, we learn a lot about the experience of living under any set of conditions by reflecting upon the desires which those conditions generate and yet leave unfulfilled. For that is the space which utopia occupies. Levitas, The Concept of Utopia, p.9

Bloch refuses the identification of utopia with a literary genre: "to limit the utopian to the Thomas More variety, or simply to orientate it in that direction, would be like trying to reduce electricity to the amber from which it gets its Greek name and in which it was first noticed. Indeed, the utopian coincides so little with the novel of an ideal state that the whole total of philosophy becomes necessary … to do justice to the content of that designated by utopia.” [Bloch The Principle of Hope, Basil Blackwell: Oxford 1986, p. 15.] Levitas, The Concept of Utopia, p. 99

Bloch would agree with Mannheim that ‘wishful thinking has always figured in human affairs’ and that ‘myths, fairy-tales, other-worldly promises of religion, humanistic fantasies, romances, have been continually changing expressions of what was lacking in actual life’. He would agree too that they have a compensatory aspect and even that they are susceptible to manipulation: the mirror in which wishful images are reflected is ‘a beautifying mirror which often only reflects how the ruling class wishes the wishes of the weak to be’. However, the compensatory aspect of wishful thinking does not in itself mean that it operates, as Mannheim supposes, to sustain the status quo. It is not merely fictitious compensation for the discomforts of experienced reality, but a venturing beyond that reality which is essential to the inauguration of a transformed future. Utopia contains compensation, but also anticipation. Levitas, The Concept of Utopia, p. 100-101