Alhassanain(p) Network for Heritage and Islamic Thought

Aristotelian Perspectives for Post-modern Reason (I)

Phronesis, Scientific Rationality and Environmental Responsibility

Alfredo Marcos

University of Valladolid

Department of Philosophy

Plaza del Campus s/n,

47011 Valladolid, Spain

amarcos@fyl.uva.es

Table of Contents

Introduction. 3

Modern Age and Actual Age: from the search for certainty to fallibilism. 7

Phronesis in Aristotle 12

Prudence and Scientific Rationality: ‘Do not block the way of inquiry.’ 15

Prudence and Environmental Responsibility: ‘May human life remain possible.’ 19

Conclusion. 23

Notes 24

Introduction

In the Modern Age, certainty became the highest and most sought-after espistemic value, even more valued than truth, and the so-called scientific method was seen as the surest path to certainty. Indeed, human reason became identified with the application of a supposed scientific method of Cartesian or Baconian inspiration. The domain of the practice became considered either one more area for the mere application of the scientific method, an application which would lead to human progress, or as an area beyond reason. One of the stereotyped convictions attributed to the enlightened mentality is this: insofar as human life in all its extremes becomes more rational, that is, more scientific, practical problems will begin to be solved. Indeed, Rousseau, in hisDiscourse on the Sciences and the Arts (1750), pointed out that human progress did not always go hand in hand with scientific and technical progress, which today is a self-evident truth that is not discussed. On the other hand, dual accounting, that is the consideration that science is fully rational and the other areas of human activity are not, as well as an insult to common sense, has rebounded against science itself, for its practical aspects cannot be hidden, and it is hardly possible to parcel off a purely logical context, as that of justification set out to be.

It is obvious that not even the application of a supposed scientific method can guarantee the progressive character of our practical decisions. To this evidence there has been added the recognition of science’s own practical aspects. This evolution has convinced many of the impossibility of obtaining certainty even in the domain of science, which has given rise to diverse forms of desperation regarding the abilities of human reasoning. This oscillation between the obsession for certainty and desperation with regard to reason has been the tune most frequently danced to in modern times.

Yet today we do not want environmental problems to be left entirely up to the expert’s decision or the irrational imposition of power or arbitrariness, but to be tackled in reasoned dialogue, on a footing of equality, by scientists, technicians, lawyers, politicians, businessmen, private individuals, representatives of social movements - and indeed philosophers! We are recognizing, at least implicitly, the possibility of being reasonable in an area where we do not expect absolute certainty, and we accept that human reason goes beyond the limits of science and technology, that reason is more deeply rooted in human life than a mere method could ever be. To reach this point we have had to come a long way as far as our concept of reason and science is concerned, and have also needed a great deal of experience - bittersweet experience - regarding the practical consequences of science. Everything would seem to show, then, that the most typical extreme positions of modern times are being abandoned, and that we have entered the post-modern period[1] .

My intention in these pages is to explore the possibilities of a project of basically Aristotelian inspiration for the integration of the theoretical and practical aspects of reason, for the search for a happy medium between the extremes of logicism and irrationalism. In my opinion, this outlook has much to contribute to the on-going debate on the rationality of science and on the environmental questions that its application brings up. This is, indeed, a particular aspect of the relationship between reason and practice, but not just any aspect: traditional philosophical problems are arising now, and they will continue to come up in the future, in direct connection with environmental matters - this will be an area and a way for the classical topics of philosophy to reappear. Rationality, good and evil, justice, the relationship between being and value, the objectivity or subjectivity of knowledge, etc., are venerable philosophical topics that we shall have to reconsider in the light of environmental problems, as they were once tackled in connection with questions of politics, theology, society, science and economy.

I shall now outline the steps that my exposition will follow, together with other considerations necessary for it to fall within the limits of a short piece. In the first place, we need a correct characterization of Modern Age which makes it possible to explain the causes of a bad relationship between theory and practice. This is an extremely complex and multi-faceted task. Here we can hardly even approach a full idea of modernity. What we can do, however, is point out one of its most essential characteristics[2] , in some wise the cause of many others and especially near to the interests of this paper. I mean the predilection for certainty, which is a constant of the modern spirit, just like the energetic and cyclic irrationalist reactions. Obsession with certainty and sceptical desperation are mutual causes of each other like pre-Socratic opposites. We shall speak of this insection 2 (‘Modern Age and Actual Age: from the search for certainty to fallibilism’) .

Secondly, we must go through the Aristotelian concepts which may, in my opinion, take us out of this thankless to-ing and fro-ing. What I mean basically is the Aristotelian notions of prudence (phronesis ) and practical truth (aletheia praktike ). Insection 3 (Prudence in Aristotle) , I shall set out the contents of Aristotelian prudence and the contribution that it can make to the present debate. An analogous study of the notion of practical truth will be set out in the second part of this paper[3] .

The concept of prudence is one that has been taken from the area of Aristotelian practical philosophy, where absolute certainty is not expected, but neither are decisions left to mere arbitrariness or imposition. The novelty consists in that, when we recognize, as we do today, that science itself is a human action, the notion taken from practical philosophy may be used for understanding and integrating scientific rationality. When science is characterized as an activity governed by prudence, it moves away from both the logicist and the irrationalist poles, from the obsession with certainty and from the ‘anything goes’, from algorithm and anarchism. Furthermore, if science is made a prudential activity, it will be much easier for us to connect its particular way of rationality with that of discussions, decisions and environmental actions.

Although it is true that Aristotelian notions can be suggestive, it is not true that they do no more than answer contemporary questions. For them to be active in the on-going debate on the relationship between theoretical reason and practical reason, they must be developed,updated through contemporary texts. The profit from this manœuvre is double: it makes Aristotle’s concepts available for the present debate and gives some contemporary ideas a very comprehensive and fertile philosophical framework, the Aristotelian framework. In the remaining sections. I shall tryto bring to the current debate the Aristotelian notion of prudence through the fallibilism of Peirce and Popper and through Hans Jonas’ imperative of responsibility. The fallibilist attitude is, to my mind, the most suitable post-modern characterization of scientific rationality and of human rationality, and applied to environmental problems it would give rise to the so-called principle of responsibility.

Insection 4 (Prudence and scientific rationality: Do not block the way of inquiry ) , I maintain that in science a fallibilistic attitude alone opens the doors to prudential reason, and that the ontological and anthropological bases of prudence are also suitable for fallibilism, founding it and encouraging it. In Aristotle, there are certain fallibilistic attitudes but they are ambiguous and combine with other statements in which science is characterized as universal and necessary knowledge. In this regard, Peirce’s texts are most useful and clearest, and, of course, nearest to the present problems of science. Fallibilism is for him an attitude, that is something practical - rather than a concept or a rule it is the scientific attitudepar excellence . On the basis of the fallibilist attitude there stands what may be the ultimate and most universal rule of scientific rationality:Do not block the way of inquiry .

Insection 5 (Prudence and environmental responsibility: May human life remain possible ), I set out to bring the Aristotelian idea of prudence to the on-going debate on the environment. I shall proceed as in the previous case, showing its proximity to and continuity with the present notion of responsibility as treated by Hans Jonas. Again we have an Aristotelian concept that can be developed or, as Jonas himself would say, improved on, by a notion of today. In return, this present notion is supported by a very articulate and coherent ontology. Jonas sets out the so-called principle of responsibility as the ultimate element of the moral control of our relationship with the environment:Proceed in such a way that you do not endanger the conditions for humanity’s indefinite continuity on Earth .

I consider that Peirce’s and Jonas’s formulations - each in its own area, respectively that of science and that of ethics - the expression of one and the same attitude, of one and the sameactual - and therefore post-modern - way of understanding rationality, and that both fit perfectly into a metaphysical framework of Aristotelian inspiration. Essentially, these ideas are convergent, and respond to one attitude and may be based on one Aristotelian conception of reality, and together they offer a good answer to questions for their scientific rationality and their environmental responsibility.

The principles of Peirce and Jonas can, however, be taken as inadequate as a characterization of human action, for they do not take into account its creative aspects. The truth is that both, though they do not guarantee it, are directed towardscreative discovery : they set out to ensure that it will be possible at any moment, while nurturing and fomenting the conditions for it and removing obstacles. They uphold the openness of human action so that it can adjust to the future course of events, always open and never completely determined. The present article will therefore require a later development in which the notion of creative discovery is tackled along with its connection with the Aristotelian concept ofpractical truth .

Modern Age and Actual Age: from the search for certainty to fallibilism

Among the characteristics of modern thought is the predilection for certainty[4] . The search for certainty has been one of the signs of identity of a whole intellectual tradition, of what Husserl[5] calls ‘European science’. According to Husserl, the abandonment of this search steeps us in crisis, in scepticism or in any type of naturalism. However, as Kolakowski[6] rightly observes, neither Descartes nor Husserl managed to distinguish between the subjective feeling of evidence and the objective evidence of truth. Consequently, in many of the modern philosophical traditions, the pursuit of certainty has become a threat to the pursuit of truth, an impulse towards different types of idealism and a cause of crisis (by inference and by reaction) rather than an antidote to it.

The pursuit of certainty -infallibilism , in the words of Laudan - is one of the legacies of Cartesian philosophy. One could state, as Clarke does, that Cartesian science is defined in terms of certainty rather than in terms of the truth of the explanations proposed.[7] A text in which Decartes himself sets this point out clearly is:

‘What can it matter to us for something to be absolutely false if anyway we believe it and we do not have the slightest suspicion that it is false?’[8]

Or, if a negative formulation is required, ‘any knowledge that can be rendered doubtful must not be called scientific’[9] and ‘I treat [...] as false everything which is merely likely’[10] These words give the tone of what would from then on be the object of the quest for the scientific method.

It is, in any event, a question of establishing methods whose results will be certain knowledge, methods which we can only trust, whether or not subjective certainty is accompanied by objective truth.

Francis Bacon initiated another route of access to certainty, this time with an empirical and inductive character. According to Bacon, the inductive method is theart of invention andmachine , as well asformula ,clear and radiant light [11] , and other similar boons. Those of Bacon’s ideas with the greatest influence on subsequent scientific thought are those which he expressed in his second book of theNovum Organum , that is his inductive logic, the so-called Baconian method. In general, and as Rossi states, many have seen in Bacon the constructor of a gigantic ‘logic machine’ doomed to not being used. With the Baconian method, according to Spedding, we cannot do anything. We consider it a subtle, elaborate and ingenious mechanism, but one which can produce nothing[12] . In spite of everything, Bacon’s image as the founder of the new science thanks to his discovery of the inductive method was greatly appreciated by the founders of theRoyal Society and the authors of the great illustratedEncyclopædia .

In what situation do we place the practical with regard to rationality when the first value is certainty?

Many modern thinkers begin their writings with the observation of the disappointing state of the philosophy of human things in comparison with natural philosophy, that is the natural science. Dissension and lack of certainty, both in metaphysics and in moral philosophy, are the points causing the greatest unrest. Both Descartes and Hume, to mention two of the most noteworthy, feel that the model that inquiry into mankind should follow is that of natural and formal sciences, which have already opened up a path, a method to certainty and consensus. So, Descartes set out to find ‘the highest and most perfect moral science, which, presupposing a knowledge of other sciences, is the ultimate degree of wisdom’[13] . Naturally, Descartes had to settle indefinitely for what he called  ‘provisional morals’. Hume stated with his empiricist approach base on the inductive method, ‘Where experiments of this kind are judiciously collected and compared, we may hope to establish on them a science which will not be inferior in certainty, and will be much superior in utility to any other of human comprehension’[14] . This science will imply the extension of the principles of Newtonian natural philosophy to the study of human nature, and within it to the study of morals. Regarding politics, Hume has still fewer doubts, and states categorically that it can be reduced to a science endowed with a degree of certainty almost as perfect as that of mathematics[15] .

But this naturalist approach to the study of man, which in principle promises the so longed-for certainty, leads to further disappointments and carries with it the germ of its own destruction, in the long term threatening natural science itself, which will always be an activity and product of human freedom and reason. Today we know from experience how these tendencies implicit in the naturalist position itself have been developed, but in Hume, the whole trajectory is already indicated. Naturalization of moral studies seems to demand a methodological reduction of the normative and the evaluative, which will end up being established as a definitive ontological reduction of human reason and freedom, which are mutually inseparable and inaccessible to the empirical method and never totally explained from strictly naturalist bases. Thence are derived an emotivism and an irrationalism which threaten science itself insofar as its practical aspects are recognized along with its inability to produce absolutely certain knowledge. Hume assures that ‘We speak not strictly and philosophically when we talk of the combat of passion and of reason. Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them’[16] . Paradoxical though this may seem, this resignation that the practical should be the place for feelings derives from a reduced notion of reason, excessively bound up with a given idea of science and method and an extreme valuation of certainty.

In Hume there is no renunciation of certainty, the basis of which is confided to habit, but one of reason. Predilection for certainty leads Hume to irrationalism, not to scepticism[17] . Karl Popper sums up the situation as follows, saying that, according to Hume, the scientific method is inductive, but:

‘... induction is completely invalid as an inference. There is not a shadow of a logical argument that would support the inference to a generalization from statements about the past (such as past repetitions of some 'evidence'). He [Hume] said that in spite of its lack of logical validity, induction plays an indispensable part in practical life [...] Thus there is a paradox.Even our intellect does not work rationally '. [p.94] [...] This led Hume, one of the most reasonable thinkers of all time, to give up rationalism and look at man not as endowed with reason but as a product of blind habit. Acording to Russellthis paradox of Hume's is responsible for the schizophrenia of modern man ’. [p.95][18]

If anything can be learnt for the present it is that we lack a notion of practical reason that is well structured and free of traditional errors. Practical criteria cannot depend on a supposed scientific method and cannot aspire to confer absolute certainty on our decisions, but we do not have to go without reason in practical situations, as there is no need to identify reason with a supposed scientific method or with the sure way to certainty. In part, the obstacles encountered by Hume and Descartes in the development of an idea of practical reason have been abolished, for today we are aware that sciences are not governed strictly by the Cartesian method or by the inductive method, and that they are far from reaching complete certainty, which does not make them directly irrational. Above everything else it is the renunciation of the obsession with certainty that enables us today to imagine a suitable notion of practical reason.

It will be said that a notion of practical reason already existed in Kant. And this is so. But two observations must be made in this regard. In Kant, unlike in Hume, there is a radical denaturalization of practical reason, which today seems unacceptable. Such is the case that for Kant, prudence mainly has nothing to do with practical reason, but with theoretical reason, paradoxical though this may seem. This means that he excludes it from the nucleus of morals and considers it a mere technical ability for the pursuit of happiness[19] . In the Modern period, from Descartes to Bacon, any technique was considered to be no more than applied science, and that if any problem arose in practice, it was due to deficiencies in theory. This view of science as immediately applicable soon spread, as we have seen in Hume, to morals, so the application of a science of man, which would not present genuinely technical problems, but only theoretical ones, would solve the problems of human happiness. Philosophers of the Enlightenment felt attracted by this new way of approaching human affairs. Kant shared the technological optimism of his day although he was the first to resist the concept of morals as a technique, that is, as the application of a science of man to the pursuit of happiness (happiness, by the way, previously defined by that very science). Kant, on the other hand, sought to protect morals from influences external to the very freedom of the subject. He did this by excluding the traditional contents from the nucleus of practical philosophy. According to Kant, prudence lies rather in theoretical reason, as it could become a mere applied science[20] . In the interests of autonomy of reason, Kant separates morals radically from nature, setting it in the sphere of the freedom of the subject. The attempt to protect morals from naturalism leads to the new excess of putting it in the hands of logicism. The categorical imperative is, at root, of a logical character:Behave in such a way that you might also want your maxim to become universal law . The ‘might also want’ invoked here is, as Jonas[21] states, that of reason an its concord with itself, an ability which would only be negated by self-contradiction.

In Aristotle, on the other hand, happiness is man’s natural and legitimate aim, whereby it was possible, according to Aubenque, ‘to integrate thetechnical moment of the correct choice of means in the definition of morality’[22] .

The second observation concerns the certainty of what Kant takes to be really practical. No comparison can be made between the splendid certainty which Kant attributes to Newtonian science and thepractical faith in postulates necessary to give consistence to the practical use of reason. In an atmosphere of extreme valuation of certainty and of the scientific method, the Kantian foundation for practical reason, which, in short, leads to the postulates of human freedom, the immortality of the soul and the existence of God, was not believed or taken seriously. Kant expressed his admiration and  respect for two areas of reality,the starry sky above me and the moral law inside me . But to keep them separate is not sustainable, for indeed he who looks at the stars and grasps moral law is a human being who takes part in the two areas of reality, as a system subject to physical laws and as a free being. The integration of the two spheres seems necessary without the negation of either of them. But if we separate to such an extent the degree of certainty that we attribute to the knowledge of each of them, and if we set such a high value on certainty, then the so-called practical use of reason runs the risk of immediately being seen as one more mask of the irrational, as a concession of Kant’s to his beliefs, affections, desires or interests. The historical proof that this two sets of accounts cannot be tenable for long is what happened to Kantian tradition. Either it tended towards an idealism that suppressed the peculiarity of the practical and made it depend for everything on theory by identifying the rational with the real, or it drifted towards an irrationalism in which the pure use of reason had the same fate as the practical use, until it was seen as one more mask of the will to power[23] . The pure and practical uses of reason must be integrated and must support each other, for today we know that they either stand or fall together[24] . But this requires a reconsideration of the ideal of certainty and of the nature of science which has only come about in the twentieth century.

Since Hegel and since Nietzsche, several campaigns have been launched in the pursuit of certainty. One of the last ones in favour of certainty, automatism and the segregation of the practical, based on the identification of reason with science, was called Neo-positivism (and it was pursued as the so-calledreceived view ). Its internal decadence apart, it was Popper’s philosophy and Kuhn’s criticisms that put an end to this venture, and with it to a way of making philosophy of science. Kuhn laid forth the practical aspects of scientific rationality. As he states - in my opinion, rightly - ‘Recognizing that criteria of choice can function as values when incomplete as rules has, I think, a number of striking advantages [p. 331] .’[25] . In Popper, a clear renunciation of the ideal of certainty and a re-instatement of truth are to be notice.

The recognition of the practical implication of science, both in its genesis and applications and in its justification, and the renunciation of the idea of certainty no doubt mark the end of the epoch in which the supposedly scientific method was shown as the zenith and model of human reason, where all philosophy aspired to ideal of certainty or took its failure as the failure of reason, first in the practical terrain and then, as an inexorable consequence, in the theoretical. Today there is an abandonment of the logico-linguistic conception of theories in favour of a pragmatic conception of science. Science, it is said, is action. But, as previously the possibility of a practical reason was not clear, nor was its articulation with theory, the rationality of science itself has been questioned. Kuhn has been accused of being relativist and irrationalist, an accusation which he has rejected, but without going so far as to construct a philosophical basis on which to base this rejection. For their parts, Peirce and Popper, each in his own way, have tackled this subject but both have recoiled, paradoxically, to quasi-Hegelian positions.

Science taken as action, as the art of research, of teaching, diffusion of knowledge and application, etc., can and must be judged with criteria that cannot in themselves be exclusively scientific or merely arbitrary, but a part of the general rationality of human life. The birth, then, of new disciplines, of new ways of making philosophy of science, such asbioethics ,environmental ethics andSTS studies , is not just a collateral phenomenon, a momentary collision point between science and practical thought, but an indication of a new way of conceiving rationality itself, or at least an indication of the need for this new reason.

I believe that the time has come to perfect concepts and attitudes that have always had a vocation to integrate the theoretical and practical planes without ruling out either of them, concepts and attitudes which were born to avoid the swing of the pendulum between the logicist and irrationalist extremes (between Permenides and Heracleitus, between Charybdis and Scylla).

Phronesis in Aristotle

Aristotle characterizes prudence (phronesis ) as

‘A true and reasoned state of capacity to act with regard to the things that are good or bad for man.’[26] .

By means of this definition he distinguishes prudence from other notions. Given that it is a disposition, or state of capacity (héxis ), it will be distinguished from science (episteme ), for prudence will be knowledge linked with human action. In the second place, as it is practical (praktike ), its result will be an action, not an object, which distinguishes it from art or technique (tekhne ). The demand for rationality and truth (‘...metà lógoy alethe ’) distinguishes prudence from moral virtues and sets it among the intellectual ones. Finally, the fact that it deals with what is good and bad for mankind, and not right and wrong in an abstract way, sets prudence apart from wisdom (sophia ).

So far we have sketched the limits of the notion of prudence and others akin to it, and the points where they overlap[27] , but we must not forget that ‘Regardingpractical wisdom [phronesis ] we shall get at the truth by considering who are the persons we credit with it’.[28]

Texts about prudence suggest that it is an intellectual virtue, but that it implies experience lived, which concerns both means and ends, for its final horizon is the good life as a whole, and that it is at the service of wisdom, that is, it is an instrument for obtaining this. However, Aristotle goes as far as to say:

‘We ought to attend to the undemonstrated saying and opinions of experienced and older people or of people of practical wisdom [phronimos ] not less than to demonstrations; for because experience has given them an eye they see aright.’[29]

In general, prudence pursues wisdom and wisdom stimulates human prudence. It is best to ‘possess both, or preferably prudence’[30] . Of animals, Aristotle says that they too are prudent[31] , but as they lack wisdom their prudence is certainly limited. For all this, prudence is worth pursuing for itself, regardless of its possible usefulness, given that it is a virtue[32] .

Prudence is a virtue, and virtue, for Aristotle, is:

‘a state of character concerned with choice, lying in a mean, i.e. the mean relative to us, this being determined by a rational principle, and by that principle by which the man of practical wisdom [phronimos ] would determine it.’[33]

Virtue, therefore, is a habit or disposition to choosing the right medium between excess and shortage. But this is not easy, for the right means is not the arithmetic mean. To find it we need another rule. This rule will be the one established by the prudent man and applied just as he would apply it. In short, we cannot determine what is or is not virtuous without the concurrence of the prudent man.

The mid point is dictated by reason or by the straight rule of the prudent man. This reason or straight rule is, rather, correct reason, that is corrected reason. It is the limit to which a process of correction tends, one of elimination of errors, by relation to the end sought:

‘[...] there is a mark to which the man who has the rule looks, and heightens or relaxes his activity accordingly, and there is a standard which determines the mean states which we say are intermediate between excess and defect, being in accordance with the right rule (katà tòn orthòn lógon )’[34] .

Therefore, prudence requires experience:

‘Young men become geometricians and mathematicians and wise in matters like these, it is thought that a young man of practical wisdom cannot be found. The cause is that such wisdom is concerned not only with universals but with particulars, which become familiar from experience.’[35]

Experience is time and memory, but not just any lapse of time, but one which one has spent reflecting, trying to understand the nature of the things we see, of the actions we do and what happens to us. Experience is the memory of a time lived and thought, for it is the fruit of succeeding corrections.

But let us remember that prudence itself is a virtue and, moreover, ‘it is impossible to be practically wise [phronimos ] without being good’[36] . Therefore, nobody could be prudent without following the ruled dictated by prudence. Nobody could be prudent without having been already. This vicious circle (or virtuous one, depending on how we look on it) is resolved by education and action, that is, by action steered by somebody prudent until one becomes prudent oneself[37] .

The prudence of an experienced person serves for drawing up rules, ‘since the universals are reached from the particulars’[38] . Butmethodological prudence , so to speak, cannot consist simply of a set of rules and meta-rules for the formulation and application of rules, which in turn would generate the same problems of definition and application, but at a higher level, ‘for the error is not in the law nor in the legislator but in the nature of the thing’[39] .

Therefore, prudence also constitutes the criterion of application, interpretation and, when necessary, modification or violation of the rule. Aristotelian prudence is rooted in the indelegable experience and in responsibility - in the risk, Pierre Aubenque would say - of each human being. Man cannot cede the risk of decision and action (nor, obviously, can the scientist) to any rule or automatic process of decision.

Not even the laws of the city can be applied completely literally. Aristotle warned that such a process could lead to grave injustice. The application of the law to the case requires something very much like prudence: equity (epieíkeia )[40] .

‘The reason is that all law is universal but about some things it is not possible to make a universal statement which shall be correct.’[41]

The proper application of the law is not guaranteed by science alone, as in the case of Plato’s king-philosopher, but rather science itself, for belonging to the general, is subject to the same problems as the law in its relation with the concrete[42] .

But this does not condemn us to irrationality or to subjectivism in our practical decisions, for prudence is not science, yet neither is it simple opinion or skill[43] , it is genuine rational knowledge with the intention of objective truth. Research must be understood as a part of human action, decisions taken in it are practical decisions falling under the jurisdiction of the Aristotelian concept of practical truth, the type of truth that prudence seeks[44] .

In conclusion, Aristotle achieves a noticeable integration of knowledge and human action, of freedom and nature, as well as of the ends of science which we call instrumentalist and realist. This composition is not arrived at in the Platonic way, where the science of Ideas will be the ultimate practical guide. Aubenque assures us that:

‘in man, Aristotle does not set one against the other, but maintains both: contemplative vocation and practical demand. But the latter no longer finds its model and guide in the former, and must look on its own level for a rule which, nevertheless, will still be intellectual or “dianoetic”.’[45]

This integration is achieved, then, through prudence and practical truth: scientific research is still part of human action and, as such, is subject to the ethical rule of prudence, and to the service of the ultimate of man’s ends, happiness, which in turn consists in true knowledge, as well as co-existence[46] and a moderate degree of welfare[47] .

Science is rooted in human life, in practical values, in time and in experience through prudence, which is a virtue and is intellectual; or, more correctly, through the prudent person. Furthermore, this prudential conception of human reason is rooted in a very realistic, profound, fruitful and commonly accepted idea of human nature: ‘desiderative reason or ratiocinative desire’[48] .