SCIENCE. — The term science (Lat. scientia = knowledge, Gr. ἐπιστήμη) has always been understood to signify a knowledge (v.) that is different and more perfect than vulgar knowledge: the difference and perfection lie not so much in the object as in the manner of knowing. The nature of such particular knowledge has been variously defined according to different mentalities and the varying extent and depth of knowledge itself. According to the ancient conception, typical science is philosophy (v.); according to the modern conception, typical science is physics (v.), whose methods and characteristics other disciplines must conform to if they aspire to the dignity of science. It is clear that only the modern conception adequately distinguishes scientific knowledge from philosophical knowledge, and thus it was only with the birth of science in the modern sense (with Galilean physics) that the various articulations of knowledge—vulgar, scientific, and philosophical—were consciously grasped.
The distinction among these three forms of knowledge can be expressed by saying that the first consists in mere observation, the second in legal description, and the third in explanation and evaluation. In this formula, the autonomy of science with respect to philosophy is also expressed, though such autonomy does not exclude collaboration.
The definition of the ancient concept of science is Aristotle (v.). For the former, science is knowledge of authentic reality (intelligible, ideal) rather than of the spurious reality that is the sensible world. Science is thus constituted by emancipating itself from the service of the senses. Science is not induction (v.), physics, or hypothesis (v.); it is solely deduction (v.), philosophy (v.), and dialectic (v.) (cf. especially Respubl., VI-VII, particularly 510-34). Aristotle definitively theorizes the ideal of scientific knowledge as deduction and syllogism (v.) unfolding within the sphere of necessity and universality. The syllogism that necessarily concludes from necessary and universal premises is the unique instrument of science. Any breach of necessity and universality is a breach of the scientific character of knowing. The deductive syllogism provides, in its premise, the reason for the conclusion; hence scientific knowledge can also be defined as causal knowledge (efficient, final, material, formal causes; cf. especially Anal. post.). “Scientia de universalibus,” “scire per causas” are the formulas that for centuries transmitted the essentials of the Aristotelian concept of science. Unlike Plato, who denies it, Aristotle recognizes that a science (philosophy) of nature is possible insofar as universals (forms) are found in nature upon which the syllogism can be founded.
The concept of science as necessary syllogism endured throughout the Middle Ages. Even St. Thomas Aquinas classifies the sciences in the Aristotelian spirit, with his doctrine of the three degrees of abstraction (v.), which, by successively abstracting from individual, sensible, and intelligible matter (matter being the antithesis of universality), found physics, mathematics, and philosophy.
While the reflected concept of science remained that of demonstrative, deductive, necessary, and universal knowledge, human knowledge in fact grew richer, more complex, and more specialized along a different path from that theorized. This was of great importance, for it was precisely along this path that new ways of knowing were being attempted, which, once they had gained certainty and self-awareness, were to become science in the modern sense. Indeed, Aristotle himself offers careful descriptions of natural history (cf. De part. animal.; De gener. animal.; Hist. animal.), and in the Hellenistic period investigations began to develop (such as in biology, astronomy, and medicine) that, being unable to fit into the Aristotelian framework, remained on the margins of philosophy: experience, the great matrix of modern sciences, was thus already present at their inception. It is true that in the early Middle Ages the scientific value of experience was unrecognized, as an allegorical and mystical interpretation of nature was superimposed upon it (continuing sporadically even into the seventeenth century, as with Kepler, for example); but by the thirteenth century (Albertus Magnus, Roger Bacon, Robert Grosseteste [v.]), and even more so in the fourteenth (Ockham [v.] and the so-called terminists such as Buridan [v.], Oresme, Albert of Saxony [v.], etc.), the authentic sense of nature and the value of experience were once again securely, though slowly and confusedly, regained. It was precisely from this naturalistic direction that the new concept of science was to emerge, even though in the centuries of the renewed influence of the ancients (fifteenth and sixteenth centuries) it would still be contaminated with the animistic and magical fantasies of pseudosciences (Telesio [v.], Paracelsus [v.], Cardano [v.], Agrippa [v.], etc.).
Finally, GALILEA (v.) concluded the effort of many centuries by creating, with dynamics, the first science in the modern sense and at the same time formulating its new concept with certainty. According to Galileo, science must abandon the search for essences, for the why, for values, and limit itself to the legal description of phenomena: the law, that is, the constant relation among elements of experience, is the object of scientific inquiry, and induction is its proper method. Galileo clearly outlined the essential moments of the method: observation, hypothesis, verification. Observation, the importance of which lies not in quantity but in method. Hypothesis, which is the anticipation of the answer to the problem posed. Verification, which is the ratification or rejection of the hypothesis, carried out by nature itself through experiment (cf. Letter to Liceti, in Opere, ed. naz., XVIII, especially pp. 208, 249; Il Saggiatore, ed. cit., VI, especially pp. 232, 348-49; Dialogue Concerning the Two Chief World Systems, ed. cit., VII, especially pp. 60, 64-65, 126, 128, 171, 273). Science thus acquires its full autonomy by defining itself according to its own object and method. It is important to note that this structure of science is made possible by considering reality solely in its quantitative aspect: hence the valorization of mathematics (v.) as an indispensable element of science. Only through mathematics is experience rationalized and necessitated; and thus without mathematics there is no science. It is in this respect especially that Galileo’s break with Francis Bacon (v.), often considered the founder or co-founder of modern science, is apparent. Bacon (cf. especially the Novum Organum) neither suspects the law nor the role of mathematics nor the experiment. He still operates within the sphere of qualitative and essential inquiry, though he merits credit for clearly denouncing the sterility of the deductive method and calling for observation and experience. A denunciation and call that, however, had already been made ELEUSIO (v.) and, more adequately, LEO, LEONARDO (v.), the true precursor of Galileo.
The history of the concept of science in the 17th and 18th centuries shows oscillations around the balance of experience and reason, so admirably defined by Galileo. Philosophers, whether rationalists (such as Malebranche [v.] and Spinoza [v.]) or empiricists (such as Locke [v.] and Condillac [v.]), reintroduce the now outdated concept of science as deductive and a priori knowledge, which in the latter case even resolves into a nominalistic and tautological systematization. Descartes himself (Discourse, part 4; Meditations, III; Principles, preface and I, particularly I. III § 43-44; also Rules, III, V), moreover, conceived physics as a deduction from the concept of intelligible extension, even though this very concept allowed him to incorporate mathematical treatment and thus to valorize the Galilean principle. Rather, among scientists, the Galilean legacy continued alongside the legacy of the concept of science itself, with an emphasis on the experimental aspect. Thus Newton enunciates the canons of a methodological procedure in which the anticipatory and rational moment is somewhat minimized ("hypotheses non fingo") in favor of an extension of the orienting and conclusive efficacy of experience (cf. generally Philosophiae naturalis principia mathematica, especially I. III, beginning and end, and Opticks, I. III, especially qq. 28 and 31). The Newtonian approach predominates in the 18th century just as the Cartesian approach had predominated in the previous century.
With a completely new approach, Kant (v.) seeks to reproduce the Galilean equilibrium: the autonomy of science with respect to philosophy, the synthesis of experience and reason, and the rationalization of experience. Autonomy, however, is separated in the dualism of phenomenon (v.) and noumenon (v.); the synthesis of experience and reason is no longer methodological but becomes structural; and the rationalization of experience becomes its (universal) subjectivization. Thus the way is opened to Romanticism (v.), which, on the basis of idealistic subjectivism, transforms—while taking it up again—the univocal concept of knowledge, in which science becomes a moment, more or less authentic, of philosophical (deductive, a priori) knowledge. Positivism (v.), while accepting the same thesis of the univocity of knowledge, reverses the position by seeing philosophy as a moment of the authentic knowledge that is scientific (experimental, a posteriori) knowledge. By vindicating the experimental and inductive character of science, positivism has reaffirmed with greater rigor its descriptive and law-like nature. It can be said that in positivism there begins that critical equation of scientific procedures that focuses above all on the care to avoid problems that exceed the scope of descriptive legality and to eliminate from the meanings of words any content that is either meta-empirical or approximate, which they unconsciously carry. But the narrowness of the gnoseological premises prevented positivistic science from justifying itself as universally valid knowledge, and the positivistic law from presenting itself as a formula of necessity; while the pride—though not entirely unjustified—over the marvelous scientific progress of the 19th century led the less cautious to canonize the complex of scientific theories of that time as the true and absolute representation of the universe, and to define, consequently, the processes and methods of science as the only valid use of cognitive instruments.
A reaction could not fail to come that would restore science to a more exact awareness of its own nature and limits. This occurred toward the end of the century from the side of both philosophers and scientists who, against the positivistic claim, formulated the new thesis of the practical and not theoretical value of science (cf. E. Boutroux, De la contingence des lois de la nature, Paris 1874; E. Mach, Analyse der Empfindungen, Vienna 1886). This thesis, extended to mathematics by Poincaré ([v.] Science et hypothèse, Paris 1902; id., La valeur de la science, ibid. 1905), and to knowledge in general by pragmatism ([v.] Peirce, James, Dewey), became one of the characteristic gnoseological theses of contemporary thought, taken up again by modern irrationalist and anti-intellectualist philosophies, and also by rationalist and idealist ones (e.g., B. Croce). The boldest and most current developments of the new concept of science are found, also under the influence of the most recent revolutions in scientific theories (relativity, quantum theory, probabilism), in the formalist and neopositivist schools (R. Carnap, Logische Syntax der Sprache, Vienna 1934).
According to the formalist approach (Russell, Hilbert, etc.), science must strive, as its goal, to become formalized, that is, to constitute itself as a hypothetico-deductive system in which the principles of deduction renounce any intuitive content and the very process of deducing is resolved into pure rules of transformation. Thus science loses its concern for content and truth, while the demand for form and exactness is exalted, until it arrives at perfect scientificity in a perfectly empty and perfectly exact schema, significant in itself by nothing. Parallel to this tendency, which is especially strong among mathematicians and with regard to mathematics, is the tendency of physicists with regard to physics. They too (physicists like Heisenberg, philosophers like the Vienna Circle), while on the one hand, aspiring to perfect systematic rigor, incline toward nominalism (v.) and toward science as coherence, or at least toward the resolution of physics into mathematical formulas, on the other hand cannot cut the bridges with experience and consequently propose an operative criterion that ensures maximum rigor by delimiting the realm of the physical entity as that of the entity definable by experiment (real or ideal), that is, finally, as that of the measurable entity insofar as it is measurable. And this might be seen as a development of the Galilean concept of science if such a doctrine were not founded on empiricist-nominalist gnoseological presuppositions that neglect the non-measurable and non-experimental elements implied in every moment of science.
The theoretical value of science is still defended, however, in an idealist sense (e.g., B. Varisco, Scienza e opinione, Rome 1901; L. Brunschvicg, Le progrès de la conscience dans la philosophie occidentale, Paris 1927), in a relativistic sense (e.g., A. Aliotta, L'esperimento nella scienza, nella filosofia, nella religione, Naples 1936), in a rationalist sense (G. Bachelard, La formation de l'esprit scientifique, Paris 1938), and in a realistic sense (E. Meyerson, Du cheminement de la pensée, ibid. 1931; E. Orestano, Verità).
According to the philosopher, especially chs. 3–5; J. Maritain, Les degrés du savoir, Paris 1932, especially part 1, chs. 2, 4).
However one may judge the various positions of contemporary thought, just recalled, it cannot be denied that at least one of Galileo’s achievements has remained generally in them: the autonomy of science with respect to philosophy. And, consequently, also with respect to religion (v.): and thus today one is generally persuaded of the unity of the supposed conflict between science and faith (v.), which so preoccupied the generation of the last century. It is perhaps to be feared, on the contrary, that autonomy may become estrangement and indifference and incomprehension, threatening the unity of the spirit and the harmony of the subject. For further references see also: CONOSCENZA; ESPERIENZA; IDEA; METODOLOGIA; NEOPOSITIVISMO; VERITÀ.
SCIENCE AND FAITH. – The question of the relations between faith and science—relations of harmony or conflict—has had very stormy periods during the 19th century; nor can it be said to have ceased to be hotly debated even in the 20th century down to our own day. The cause is to be sought in the influence exerted by the various philosophical theories that have gradually gained vogue (idealism, historicism, existentialism, positivism, relativism, scientism) and in the impulse derived from the emergence of ever new hypotheses in historical and scientific matters, too hastily and greedily accepted and endorsed as unshakable theses, out of naivety, ignorance, desire for novelty, or other motives, whether open or concealed, but always outside the strictly scientific field.
The alleged conflict between science and faith would arise from the fact that faith, with its method of authority, its dogmas intolerant of progress, evolution, and adaptation to modern thought, and its immutable fixity, does not accord, indeed cannot accord at all, with science, which is ever in motion with its procedures of free inquiry and free criticism, entirely intent on progress, on revising outmoded positions, and on ever broader and deeper investigations. The consequences are: the Catholic, who wishes to remain truly such, can never be a true scientist; a kind of dichotomy of the Catholic is necessary, in the dual personality of believer and critic or scientist; and the conflict between science and faith must culminate in the full realization of Voltaire’s motto: “ceci tuera cela,” understanding naturally by “ceci” science and by “cela” faith.
1. **The Position of the Church.** – The Church’s stance regarding this alleged conflict and the vagueness of the terms in which it is draped is as simple and straightforward as possible and has been clearly expressed in the Vatican Council (Session III, *De fide catholica*, chap. 4 [Denz.-U., no. 1799]): a) faith and reason can never dissent from one another; rather, they mutually assist each other: properly applied reason demonstrates the solidity of the foundations of faith; faith, in turn, frees and preserves reason from error and enriches it with many insights. b) The Church is so far from hindering the study of the arts and sciences that, on the contrary, it promotes and aids them in many ways. c) Nor does it forbid each discipline from employing and applying within its own sphere the principles and methods proper to II. d) While recognizing this legitimate freedom for science, the Church nonetheless prevents it from accepting errors contrary to divine Revelation and from overstepping its own boundaries to invade the field of faith and sow confusion. The Church’s position, therefore, is entirely in favor of the agreement and harmony between the two fields, against any supposed and absurd dichotomy, because its starting point is clear: God, as the author of both the natural and supernatural orders, of Revelation and of science, cannot possibly contradict Himself, nor reveal a truth that is contrary to science when that science is true science.
2. **The Position of the Adversaries.** – The position of the adversaries, however, is not so clear and straightforward, given the confusion that reigns in their premises, although all agree in concluding that it is impossible to be both Catholic and a lover of free and modern culture. The main objections are outlined below, followed by their refutation.
a) Science, the advocates of the alleged conflict claim, must be entirely free, must not obey preconceived ideas, nor accept imposed solutions. Now, the Catholic scientist, if he wishes to remain such, will necessarily have to approach history, philosophy, ethnography, etc., with ideas already imposed and determined (the dogmas and doctrines of the Church) and therefore preconceived; this robs his research and conclusions of all scientific value. The reply is easy: these same adversaries, who so pride themselves on extolling the full freedom of their investigations, are themselves victims of a prejudice, of a preconceived idea, because every rationalistic procedure is dominated (whether they admit it or not) by their own negative and absolute premise: the exclusion of the supernatural and the possibility of a real transcendent being, the impossibility or ahistoricity of divine Revelation. The materialist, who denies God because He is transcendent and not immanent in the universe; the rationalist, who seeks to demonstrate how God does not enter into the governance and history of the world; the evolutionist, who asserts that man derives his soul and body from the beast—all obey principles that they themselves acknowledge unconsciously; they follow or create their own philosophy; in other words, they obey preconceived ideas. Moreover, it must be said that every scientific work necessarily presupposes a certain number of preconceived ideas: the historian must have a certain conception of the world and life; the philosopher cannot prescind from the truths proclaimed by common sense; the scientist must start from positions already scientifically proven by earlier scientists, lest, if he wishes to retrace the entire path from the beginning, he make no progress in science.
Nor should the scientific character of a work be judged a priori by whether its conclusions are favorable or unfavorable to the ideas of the adversary; rather, to determine whether it is scientific or not, one must examine the method by which it was composed, whether it was conducted according to the principles and laws of that particular science.
As for those who would argue that the impossibility of the supernatural is a certainty now acquired philosophically, it may be replied that for the Catholic the possibility of it is also a certainty acquired philosophically; here everything depends not on an a priori assertion about the value of a given philosophy, but on the documented and evaluated proofs on which it is based.
b) The Catholic, it is objected, is never merely a scientist but is also an apologist; he does not seek the truth for its own sake but in function of defending his beliefs, and this apologetic concern falsifies his judgment. It may be granted that some Catholic scientists also have apologetics in view, as indeed
In the opposing camp, where proofs and facts are all too readily bent to defend a particular theory—e.g., Marxist or monist (one need only think of the mountain of fabulous claims assembled by Draper and presented as historical truths, or the celebrated falsifications introduced by Haeckel in the series of embryos)—not all Catholic scientists are apologists. Instead, they strive to verify and document facts, allowing the truth to defend itself by merely appearing in the clear light of their exposition. Here too, one need only observe whether the methods and principles peculiar to the sciences were truly followed and deduce the scientific character—or lack thereof—of the work from the outcome of this scrutiny.
c) The Catholic is not free in his research because his conclusions are already imposed upon him in advance by an external authority. The answer requires a distinction. First, it must be noted that Revelation does not in any way take the place of scientific procedures, as though depriving them of their raison d’être, nor does it teach the sciences positively by fixing their principles and methods. Its sole task is to make known—and therefore to reject as errors, insofar as they contradict the infallible testimony of God—many positions and conclusions that a philosopher or scientist might be tempted to accept as scientific truths or at least as hypotheses awaiting further proof (cf. Pius XII’s encyclical *Humani generis* of 12 August 1950, in the section concerning polygenism: *AAS*, 42 [1950], p. 576). The Catholic scientist must keep the divine Revelation before his eyes like a star guiding his path, whose light will serve to warn him of the reefs to be avoided” (Letter of Pius IX to the Archbishop of Munich, 21 December 1863 [*Denz-U*, no. 1681]).
When the Church intervenes in such cases, she does not sit among the scientists as one of their number; rather, she speaks with the authority of God the Revealer, as one commissioned from on high to preserve from error and deviation. Now, there are conclusions that belong exclusively to pure science, and in these the Church does not intervene (e.g., she does not dictate laws to the scientist studying electricity or biology within their proper domain); but there are also conclusions that belong to a mixed domain, that is, to both science and faith (e.g., the origin of man, the spirituality of the soul, the descent of the human race from a single primitive stock: Adam and Eve, etc.), and in these the Church intervenes to prevent errors and deviations.
Nor does the scientist, as a Catholic, accept the fact of Revelation and the authority of the Church without solid and unshakable reasons. Nor does he confuse what is dogma with the philosophical, exegetical, and historical proofs adduced in support of the dogma when the Church’s Magisterium has not pronounced on them. In this way, he possesses perfect unity in his thought and is not forced unnaturally into two alien persons: the believer and the scientist.
d) A final objection: when the Catholic undertakes the examination of religious facts, he not only admits from the outset the possibility of Revelation but already acts on the basis of its reality; in other words, the facts he adduces as rational proof for assent to dogma are already seen by him in the light of that dogma. The response is that nothing prevents dogmas, already accepted by the mind, from influencing or being able to influence in some way the orientation of our research. Why should the believer not also strengthen his faith through a purely rational and autonomous process when this is possible? Why should he not begin from purely rational principles and arrive at rational conclusions that perfectly coincide with his faith? Indeed, the existence of God, which is a dogma of faith, can and must be admitted even through a purely rational process; therefore, the Catholic scientist is not in the least diminished if, by another path—the path of faith—he already knows in advance the goal to which he must arrive.
3. The Religiosity of Science — In two addresses on scientific topics delivered by Pius XII to the Pontifical Academy of Sciences (22 November 1951; *AAS*, 44 [1952], pp. 31–43) and to the World Congress of Astronomy (7 September 1952; *ibid.*, pp. 732–39), the Holy Father wished to address another question as well: that of the religiosity of science. On the one hand, scientific investigations, by revealing the intrinsic mutability and contingent structure and function of the cosmos, reaffirm the objective validity of the historical and rational arguments for the existence of God, now reconsidered on a broader, more critical, and deeper empirical basis. On the other, the conquest of cosmic space has demonstrated the limitations of scientific knowledge, the finitude of the inquiring spirit and of the cosmos itself, so that man must halt before insurmountable frontiers; hence the necessary affirmation of the existence of God, the eternal Creator Spirit.
Science is therefore “religious” because it is “bound to God,” both in the object of its inquiry (the cosmos) and in the cognitive search (the human spirit). Cosmos and human spirit, though on essentially different planes, are finite beings brought into being by creation and therefore point back, through a causal deductive process, to God. Consequently, the reconciliation between faith and science presupposes two principles: “the first, that the method of the sciences is valid only within the sphere in which they are truly competent, namely, that of the senses; the second, that beyond physical knowledge and realities there are other—metaphysical—realities (e.g., causality) that do not depend on sense data but on universal ontological laws. These, far from being inferior in certainty to the laws of the sensible world, are superior to them, since they hold for every being as such. Now they lead with irresistible force to the natural knowledge of God” (Speech of His Holiness Pius XII to the students of the Studium Urbis, 15 June 1952).
S. E. TECHNICS — By the expression “scientific-technical progress,” understood in a very broad and varied sense, we mean here “the ever-growing patrimony of scientific discoveries and technical applications achieved by humanity over time.” From a moral standpoint, in order to answer the central question—“whether it is good for men to enjoy an ever-increasing quantity of scientific discoveries and technical applications”—it is necessary to make some clarifications and distinctions.
First of all, a distinction must be made between science as such—that is, thorough and disinterested inquiry into natural phenomena in order to know their causes and laws—and technology as quantitative, practical, and economically efficient utilization of the forces and goods of nature. Even when reference is made to “men” who may “benefit” from technical progress, it must be clarified whether this refers to a few men or to the greatest possible number, to certain nations or to all peoples, to certain social classes or to all, and whether this is to be understood merely as a right or also as actual implementation.
At least tendentially, when reference is made to men, all men must be understood: every discrimination runs counter to a requirement of social justice, which must be realized not only with regard to access to economic goods, but also with regard to access to science and the use of technical means. Today, immense sectors of humanity still lack scientific knowledge and possible techniques, due to economic deficiencies and imbalances, but also because of a lack of interest on the part of public authorities and of individuals or communities who do not understand their importance and urgency. There is not the same enthusiasm for scientific and technical knowledge as there is, for example, for other rewards, for the possession of economic goods, and even, to a lesser extent, for literary and artistic culture; whereas the very “humanistic” culture of today cannot disregard scientific and technical knowledge, since both form the environment in which the “real man” of today lives.
With this premise, several observations will facilitate a proper moral evaluation:
1) Every scientific-technical knowledge and device is by its nature a means and must never become an end in itself;
2) Science and technology have an intrinsic autonomy: their laws are realities and truths in themselves, and as such, if maintained within their proper sphere, possess an absoluteness that is not subject to external influences or corruption.
From the first observation it follows that no moral judgment can be passed on technical progress as such, except in relation to the ends to which it is put to use: neither electric power, nor a new metal alloy, nor an ingenious mechanism, nor even the atomic bomb is subject to moral judgment—everything depends on the use to which they are put, that is, on the ends toward which such means are directed.
From the second observation it follows that science and technology contain laws that cannot be altered by human will, nor hidden or falsely presented without violating a fundamental honesty. Especially science, as disinterested research into truth, is a commitment of man, endowed by God with intelligence and a vocation to inquiry. From this perspective, every discovery is always a good and a reason to give glory to God. With regard to technology, since its problems are always intertwined with economic ones, the moral judgment on a technical application must take into account its economic effects: in particular, whether it yields honest or dishonest, individual or social, immediate or future benefits.
When, then, in judging technology one turns to the “technicians” themselves, a third observation must be added:
3) Every scientist or technician is always and above all a man. Even though technology is a means, the technician, as a man, must never, by himself or by others, be reduced to the level of a mere instrument. At no moment can he be indifferent to the results of his work: while as a technician he has the duty to perform his work with scrupulous objectivity, as a man he must take a stand regarding the free choices that men may make of the possibilities offered by technology.
A fourth and final observation can be made in defense of technology against the pessimists:
4) Technology, in itself, is a means to free man—all men—from material necessities and to allow him to devote himself ever more to the needs of the spirit. If this does not seem to be happening today, the fault is not to be found in technology but rather in the will of men.
In substance, as the means at man’s disposal increase, so do his temptations (understood as external challenges; the interior problem, of course, is not necessarily linked to such external challenges). And although this does not, in itself, constitute a worsening of the situation—since it also increases the merits of those who resist—it is necessary to be deeply concerned with the necessary moral strengthening of man, on both the natural and the supernatural planes, so that he may be able to resist the strongest pressures to which he is subjected. That is to say, moral progress must keep pace with technical progress.