In an article published in 1928, José Carlos Mariátegui, the true founder of Latin American Marxism, wrote: "Of course, we do not want socialism in Latin America to be an imitation or a copy. It must be a heroic creation. We must inspire Indo-American socialism with our own reality, our own language. That is a mission worthy of a new generation."  His warning went unheard. In that same year the Latin American communist movement fell under the influence of the Stalinist paradigm, which for close to a half century imposed on it an imitation and copy of the ideology of the Soviet bureaucracy and its so-called ’actually existing socialism’.
We do not know whether Che was acquainted with Mariátegui’s article. He may have read it, for his companion Hilda Gadea loaned him Mariátegui’s writings in the years preceding the Cuban revolution. Whatever the case, much of his political thought and practice, especially in the 1960s, can be said to have been aimed at emerging from the impasse to which the servile imitation of the Soviet model had led in Eastern Europe. His ideas on the construction of socialism are an attempt at ’heroic creation’ of something new, the search - interrupted and incomplete - for a distinct model of socialism, radically opposed in many respects to the ’actually existing’ bureaucratic caricature.
From 1959 to 1967, Che’s thought evolved considerably. He distanced himself ever further from his initial illusions concerning Soviet or Soviet-style socialism, that is, from the Stalinist version of Marxism. In a 1965 letter to a Cuban friend, he harshly criticized the ’ideological tailism’ that was manifested in Cuba by the publication of Soviet manuals for instruction in Marxism. These manuals, ’Soviet bricks’ to use his expression, "have the disadvantage of not letting you think: the Party has already done it for you and you have to digest it."  Still more explicit, especially in his post-1963 writings, is his rejection of the ’imitation and copy’ and his search for an alternative model, his attempt to formulate another path toward socialism, one that is more radical, more egalitarian, more fraternal, more human and more consistent with the communist ethic.
Che’s death in October 1967 interrupted a process of independent political maturation and intellectual development. His work is not a closed system, a polished system of thought with an answer to everything. On many questions, such as planning, the struggle against bureaucracy and so on, his thinking remains incomplete. 
The driving force behind this quest for a new road - over and above the specific economic issues - was the conviction that socialism is meaningless and consequently cannot triumph unless it holds out the offer of a civilization, a social ethic, a model of society that is totally antagonistic to the values of petty individualism, unfettered egoism, competition, the war of all against all that is characteristic of capitalist civilization, this world in which ’man eats man’.
The construction of socialism is inseparable from certain moral values, in contrast to the ’economistic’ conceptions of Stalin, Krushchev and their successors, who consider only the ’development of the productive forces’. In a famous interview with the journalist Jean Daniel, in July 1963, Che was already developing an implicit critique of ’actually existing socialism’: "Economic socialism without a communist morale does not interest me. We are fighting poverty, but at the same time alienation.... If communism is dissociated from consciousness, it may be a method of distribution but it is no longer a revolutionary morality." 
If socialism claims to fight capitalism and conquer it on its own ground, that of productivism and consumption, using the weapons of capitalism - the commodity form, competition, self-centred individualism - it is doomed to failure. It cannot be said that Che anticipated the dismantlement of the USSR, but in a way he did have the intuition that a ’socialist’ system that does not tolerate differences, that does not embody new values, that attempts to imitate its adversary, that has no ambitions but to ’catch up to and surpass’ the production of the imperialist metropolises, has no future.
Socialism, for Che, represented the historical project of a new society based on values of equality, solidarity, collectivism, revolutionary altruism, free discussion and mass participation. His increasing criticisms of ’actually existing socialism’, like his practice as a leader and his thinking about the Cuban experience, were inspired by this communist utopia, in the sense given this concept by Ernst Bloch. 
Three things express in concrete terms this aspiration of Guevara and his search for a new path: the discussion on the methods of economic management, the question of the free expression of differences and the perspective of socialist democracy. The first clearly occupied a central place in Che’s thinking, while the other two, which are closely related, are much less developed, with some lacunae and contradictions. But they are ever-present in his concerns and his political practice.
1. The methods of economic management
This refers to the famous discussion in 1963-64 concerning various aspects of planning, in which he found himself in opposition to supporters of the Soviet model: the Minister of Foreign Trade, Alberto Mora, and the director of the National Institute of Agrarian Reform (INRA), Carlos Rafael Rodriguez, who were supported by the well-known French Marxist economist Charles Bettelheim. The positions of Ernesto Guevara - which were supported by the Belgian Marxist economist (and Fourth International leader) Ernest Mandel - constituted a radical critique, initially implicit, later explicit, of ’actually existing socialism’. The main aspects of the East European model opposed by Che were :
the law of value as an objective law of the economies in transition to socialism, a thesis of Stalin upheld at the time by Charles Bettelheim;
the commodity as the basis of the system of production;
competition (between enterprises or between workers) as a factor in increasing productivity;
individual rather than collective incentives and distribution methods;
economic privileges of managers and administrators; and
market criteria in the economic relations among socialist countries.
In his famous ’Speech in Algiers’ in February 1965, Ernesto Guevara called on the countries claiming to be socialist to "put an end to their implicit complicity with the exploiting countries of the West" as expressed in the unequal exchange relationships they were carrying on with peoples engaged in struggle against imperialism. Socialism, in Che’s view, "cannot exist without a change in consciousness to a new fraternal attitude toward humanity, not only within the societies which are building or have built socialism, but also on a world scale toward all peoples suffering from imperialist oppression". 
- Che in the Cuban delegation to the UN
In his March 1965 essay, ’Socialism and Man in Cuba’, analyzing the models for building socialism that were applied in Eastern Europe, Che rejected the conception that claimed to "conquer capitalism with its own fetishes". "The pipe dream that socialism can be achieved with the help of the dull instruments bequeathed to us by capitalism (the commodity as the economic cell, profitability, individual material interest as a lever and so on) can lead into a blind alley.... To build communism it is necessary, simultaneous with the new material foundations, to build the new man." 
One of the major dangers in the model imported from the countries of Eastern Europe was the increase in social inequality and the formation of a privileged layer of technocrats and bureaucrats: in this system of remuneration, "it is the directors who always earn more. Just look at the recent proposal in the German Democratic Republic; the importance assigned to management by the director, or what’s more the director’s remuneration for managing." 
Basically, the debate was a confrontation between an ’economistic’ view, which considered the economic sphere as an autonomous system governed by its own laws like the law of value or the laws of the market, and a political conception of socialism, in which economic decisions concerning production priorities, prices and so on are governed by social, ethical and political criteria.
Che’s economic proposals - planning in opposition to market forces, the budgetary finance system, collective or ’moral’ incentives - were attempts to find a model for building socialism based on these criteria, and thus differing from the Soviet model.
It should be added that Guevara did not successfully develop a clear idea of the nature of the Stalinist bureaucratic system. In my opinion, he was mistaken in tracing the origin of the problems and limitations of the Soviet experience to the NEP rather than the Stalinist Thermidor. 
2. Freedom of discussion
In the economic discussion of 1963-64, an important political aspect that is worth noting is the very fact of the discussion, that is, the position that the public expression of disagreements is normal in the process of building socialism, or the legitimation of a certain democratic pluralism within the revolution.
This problematic was only implicit in the economic debate. Guevara never developed it explicitly or systematically, and he certainly did not link it with the question of democracy in planning. But he did adopt, on several occasions during the 1960s, a favourable attitude toward freedom of discussion within the revolutionary camp and toward respect for a plurality of opinions.
An interesting example may be found in his conduct in regard to the Cuban Trotskyists, whose analyses he did not agree with at all (he criticized them harshly on more than one occasion). In 1961, in a discussion with the North American left-wing intellectual Maurice Zeitlin, Guevara denounced the destruction by the Cuban police of the printing plates for Trotsky’s ’Permanent Revolution’ as "an error" that "should not have been done". And a few years later, shortly before leaving Cuba in 1965, he managed to free the Cuban Trotskyist leader Roberto Acosta Hechevarria from prison, taking leave of him with a fraternal greeting: "Acosta, you can’t kill ideas with blows." 
The clearest example is his reply, in a 1964 report to his comrades in the Ministry of Industry, to the charge of ’Trotskyism’ levelled against him by some Soviets: "In this regard, I think that either we have the capacity to destroy contrary opinions with arguments or we should let them be expressed.... It is not possible to destroy opinions by force, because that blocks any free development of intelligence. There is much that is worthwhile in Trotsky’s thinking, although it seems to me that his fundamental conceptions were wrong and his later action mistaken." 
It is no accident, therefore, that Guevara’s most explicit defence of freedom of expression and most direct criticism of Stalinist authoritarianism was manifested in the field of art. In his famous essay ’Socialism and Man in Cuba’ (1965), he denounced Soviet-style ’socialist realism’ as the imposition of a single form of art: "the kind of ’art’ functionaries understand". With this method, he emphasized, "True artistic inquiry ends" and "a straitjacket" is put "on the artistic expression of the man who is being born...." 
3. Socialist democracy
Although Che never managed to elaborate a finished theory of the role of democracy in the socialist transition - perhaps the major gap in his work - he rejected the authoritarian and dictatorial conceptions that did so much damage to socialism during the 20th century. To those who claim "to educate the people" from above, a false doctrine already criticized by Marx in the Theses on Feuerbach ("who will educate the educator?"), Che answered in a speech in 1960: "The first recipe for educating the people is to bring them into the revolution. Never assume that by educating the people they will learn, by education alone, with a despotic government on their backs, how to conquer their rights. Teach them, first and foremost, to conquer their rights and when they are represented in government they will effortlessly learn whatever is taught to them and much more." Or in other words: the only emancipatory pedagogy is the self-education of the people through their own revolutionary practice, or as Marx put it in The German Ideology, "The coincidence of the changing of circumstances and of human activity or self-changing can be conceived and rationally understood only as revolutionary practice."  Along the same lines are some critical notes from 1966 concerning a Soviet political economy manual that contain this blunt formula: "Stalin’s great historical crime was to have depreciated communist education and instituted the unfettered cult of authority." 
The major limitation lies in the insufficiency of his thinking about the relationship between democracy and planning. His arguments in defence of planning and in opposition to market categories are extremely important and acquire new relevance in light of the neo-liberal vulgate that now dominates with its ’market religion’. But they leave aside the key political question: Who does the planning? Who determines the major options in the economic plan? Who determines the production and consumption priorities? Without a genuine democracy - that is, without (a) political pluralism; (b) free discussion of priorities; and (c) free choice for the population between the various economic propositions and platforms that are being debated - planning is inevitably transformed into a bureaucratic and authoritarian system of ’dictatorship over needs’ (as is amply demonstrated by the history of the former Soviet Union). In other words, the economic problems of the transition to socialism are inseparable from the nature of the political system. The Cuban experience over the last three decades reveals, as well, the negative consequences of the absence of democratic socialist institutions, although Cuba has managed to avoid the worst bureaucratic and totalitarian aberrations of the other states of supposed ’actually existing socialism’.
This debate is related to the problem of the revolution’s institutions. Guevara rejected bourgeois democracy, but - notwithstanding his anti-bureaucratic and egalitarian sensibility - he was far from having a clear vision of socialist democracy. In ’Socialism and Man in Cuba’, he acknowledges that the revolutionary state may make mistakes, thereby provoking a negative reaction among the masses and forcing the state to make a correction (the example he cites is the sectarian policy of the party under the leadership of Anibal Escalante in 1961-62). But, he notes, "Clearly this mechanism is not adequate for insuring a succession of judicious measures. A more structured connection with the masses is needed...." At first, he seems to be satisfied with a vague "dialectical unity" between the leaders and the masses. But a few pages later he confesses that the problem is far from an adequate resolution that would allow effective democratic control: "This institutionalization of the revolution has not yet been achieved. We are looking for something new...." 
We know that, in the final years of his life, Ernesto Guevara had gone a long way in distancing himself from the Soviet model, in his rejection of the ’imitation and copy’ of ’actually existing socialism’. But a good part of his final writings have remained unpublished for inexplicable reasons. Among these documents is a radical critique of the Manual of Political Economy of the Academy of Sciences in the USSR, written in 1966. In an article published in 1996, Carlos Tablada, the author of an important book on Che’s economic thought, cites some paragraphs from this document, to which he had access but was not authorized to publish in full. One such paragraph is extremely interesting, for it shows that in his final political thoughts Guevara came close to the idea of socialist democracy, a democratic planning process in which the people themselves, the workers, "the masses", to use his terminology, will make the major economic decisions: "In contradiction with a conception of the plan as an economic decision by the masses, conscious of the peoples’ interests, we are offered a placebo, in which only the economic factors determine the collective fate. This is a mechanistic, non-Marxist technique. The masses must be able to direct their fate, to decide which share of production will be assigned respectively to accumulation and consumption. Economic technique must operate within the limits of this information and the consciousness of the masses must ensure its implementation." 
In October 1967, the assassins’ bullets of the CIA and its Bolivian allies interrupted this work of "heroic creation" of a new revolutionary socialism and a new democratic communism.