Bocheński’s philosophical development comprised three phases (I omit his engagement with Soviet studies as well as his political and moral views). He began as an eclectic philosopher. His PhD thesis about the concept of Ding an sich in Maurycy Straszewski, a Polish philosopher of secondary importance, symbolizes this phase.Footnote 1 This topic was suggested to Bocheński by Mark de Munnyck, a professor of philosophy in Fribourg (Switzerland). Bocheński explicitly said that he was forced to write this dissertation by de Munnyck who was his supervisor. In fact, Bocheński had a very low opinion of his PhD thesis and even suggested (in private conversations with the author) that he was ashamed of it. Bocheński’s second phase began about 1930, when he became familiar with mathematical logic. In the beginning, he taught himself this field by reading works of Bertrand Russell (Bocheński always considered the Principia Mathematica as one of the most important books for him), Kazimierz Ajdukiewicz, Alonzo Church and Haskell Curry. Reading of Ajdukiewicz resulted in Bocheński’s contacts with the Lvov-Warsaw School, particularly with works of Polish logicians. In the 1930s, he personally met Ajdukiewicz and other leading representatives of this school, namely Jan Łukasiewicz, Stanisław Leśniewski, Alfred Tarski, and Tadeusz Kotarbiński.Footnote 2 Bocheński, as a Dominican father, accepted Thomism as his philosophical background. Contacts with logicians convinced him that the traditional scholasticism should be modernized by using devices taken from modern symbolic logic.Footnote 3 This task became the main goal of the so-called Cracow Circle, a group of Catholic philosophers formed in 1936 (see below for details). The third phase of Bocheński’s philosophy (starting in the 1960s) consisted in an essential modification of his earlier views. He explicitly said that he became an analytic philosopher and did not wish to be considered as a Thomist.

Bocheński’s final philosophical views can be summarized in the following points:

  1. (1)

    Rationalism (the world is an ordered whole);

  2. (2)

    Antirelativism and antiscepticism (true knowledge is possible);

  3. (3)

    Logical account of knowledge (knowledge is a logically ordered system);

  4. (4)

    Inductivism (empirical knowledge is achieved by induction and it is fallible);

  5. (5)

    Platonism (there are ideal objects);

  6. (6)

    Anthropological naturalism (human beings are parts of nature);

  7. (7)

    Antipositivism (for Bocheński, a consequence of Platonism);

  8. (8)

    Aristotelianism (empiricism, ontology is logic, the priority of the real over the ideal);

  9. (9)

    Antirrationalism (one should reject all views which are not based on logic or empirical evidence; “Outside logic, there is only nonsense”—as he proclaimed with his very characteristic and radical exaggeration).

Moreover, Bocheński had a surprisingly great respect for Hegel and much less for Kant. He used to say that the former’s false opinions are better than the latter’s true views.

It is interesting that the points (1)–(9) do not concern religious matters. Of course, Bocheński remained a faithful Catholic to the last days of his life, although some of his religious views were not orthodox in certain respects, but I will not enter into this problem.Footnote 4 Clearly, the points (1)–(9) indicate that Bocheński radically separated philosophy from religion. Although Bocheński was interested in some problems of theology, for instance, he undertook several logical investigations into the Five Ways of Thomas Aquinas, he considered this work as purely theoretical and independent of any religion. He was ready to defend some Thomistic demonstrations of God’s existence (ex motu, for example), but he strongly criticized other (the teleological argument, for example). Bocheński regretted that Catholic theology had become increasingly irrational (he considered John Paul II as guilty of this tendency), but he did not try to act counter to this style of doing divina scientia. In his logic of religion, Bocheński pointed out that the structure of religious doctrines should be investigated in the same way as any other, that is, by means of logic and scientific methodology. This also means that the theory of religion should abstain from serving as an apology of this or that confession.

Bocheński did not define analytic philosophy by a single condensed formula.Footnote 5 He maintained that, due to a considerable plurality of currents in the analytic camp, such a definition is impossible. According to him, if one wants to characterize analytic philosophy, he or she should start with a fixed list of analytic philosophers. Bocheński cites as typical representatives of analytic thought Kazimierz Ajdukiewicz, John L. Austin, Rudolf Carnap, Roderick Chisholm, Richard R. Martin, Karl Popper, Willard van O. Quine, Nicolas Rescher, Gilbert Ryle, Heinrich Scholz, Peter Srawson, Alfred Tarski, and Paul Weingartner. The next step consists in looking for common views among the members of this group. Bocheński proposes four distinctive denominations expressed by terms (labels) as helpful for understanding what analytic philosophy is: “analysis”, “language”, “logic” and “objectivism”. More precisely, analytic philosophers perform detailed analytic works, investigate language, respect logical rules and strive to be objective. In particular, the first feature defends philosophy against its identification, very frequent throughout history, with world-views, that is, ideologies, religions, etc. This is a metaphilosophical characterization of analytic thought by Bocheński and thereby presents a scheme for doing philosophy. Now, points (1)–(9) as stated above fulfill this framework in a certain way. There is no reason to discuss here whether all these views of Bocheński agree with his general metaphilosophy or whether all the philosophers he cites can be qualified as belonging to the analytic school (for example, Popper himself did not agree to be included in the analytic camp). Furthemore, naturalism is not necessarily a component of analytic philosophy. It was accepted by Quine and Popper, but rejected by Chisholm. Similarly Carnap was a positivist but Strawson was not. Leaving such unavoidable controversies aside as depending on fairly complex interpretations, one very important thing should be noted in this context. Clearly, Bocheński’s metaphilosophical as well as his substantive views constitute a different philosophical position than that to which he cleaved during the 1930s. At that time, Bocheński wanted to improve not only Thomistic philosophy by using formal logical tools, and he also hoped to defend religion against its critics. Hence, the question arises why did Bocheński give up his earlier views? My claim is that his participation in the Cracow Circle and his subsequent recognition that the projected reform of Thomism via logic had failed, contributed to the evolution of his thought toward a-religious analytic philosophy.

The Cracow Circle consisted of four philosophers including (other than Bocheński) Father Jan Salamucha (Łukasiewicz’s student, the author of interesting works in the history of logic), Jan F. Drewnowski (Kotarbiński’s student, the author of a philosophical program recommending logic as an instrument of philosophy) and Bolesław Sobociński (Leśniewski’s student, a logician).Footnote 6 In September 1936, the 3rd Polish Philosophical Congress took place in Cracow. Father Konstanty Michalski, professor at the Jagiellonian University in Cracow and a reputed historian of medieval philosophy, invited a group of philosophers to discuss the mutual relations of Catholic thought and contemporary logic (32 persons accepted the invitation). Specially prepared papers were delivered by Łukasiewicz (“In defence of logistic”), Bocheński (“The tradition of Catholic thought and preciseness”), Jan Salamucha (“A confrontation of Scholastic logical devices and logistic ones”) and Drewnowski (“New Scholasticism and the modern requirements of science”). Next, these papers were discussed by representatives of traditional scholastic philosophy. The entire material, ordered and supplemented by the extensive replies of Bocheński (“Logistic ‘relativism’”) and Salamucha (“On the ‘mechanization’ of thinking,” “A possibility of formalization of the domain of analogical concepts”) was published in a book form.Footnote 7 Michalski, who hosted the meeting, wrote an introduction in which he said:

It is known that Rev. Zybura distributed the questionnaire concerning the vitality and non-vitality of contemporary peripatetic philosophy in the United States. Replies came from the camp sympathetic to scholasticism as well as from the opposite camp. The voices radically condemning the traditional style of philosophical thinking were not numerous. Good advice also appeared from the opposite camp. This advice was most often fruitful in its effects, because it exhibits the existing inaccuracies. Among other things, it was pointed out that contemporary peripatetic philosophy, mostly taught in seminars for priests, did not enter into a contact with new mathematical logic, although it could find in it inspiration for its own development. […]

Since one of the main centres of the creative work in mathematical logic has arisen in Poland, the relation of peripatetic philosophy to mathematical logic must necessarily be revised in our country. To pursue an ostrich policy would demonstrate our own inner powerlessness. Hence one should positively acknowledge that, on the occasion of the congress of Polish philosophers in Cracow, a separate meeting has taken place between representatives of mathematical logic and representatives of Christian philosophy for the sake of a trustful and sincere discussion of the problem.Footnote 8

The Cracow Circle arose as a result of the meeting organized by Michalski

It is perhaps interesting that a similar problem was discussed at the Cracow Congress, independently of the methodological problems of Thomism. Here is Sobociński’s report (my italics):

In Poland special conditions arose, which caused the problem of mathematical logic and its applications to philosophy to be particularly important and vital. It is a result of the fact that the largest and the most influential philosophical group consists of people who, directly or indirectly are connected with the school of Prof. K. Twardowski. He was able to impart to the philosophical community he created the conviction that in philosophy precisely defined concepts, explicitly stated assumptions and correct arguments are required. This group of philosophers, although fairly different in their philosophical views, easily grasped the need to replace traditional logic by mathematical logic. […]. Hence at the Congress in Cracow the representatives of logistic stressed that […], independently of the accepted world-view and the philosophical current, one must apply the principles discovered by logic in carrying one’s own inferences. This was strongly stressed by Prof. K. Ajdukiewicz during one discussion. He stated quite simply that […] one must be conscious that modern logic must be applied by everybody who wants to infer something responsibly, independently of assumptions underlying the given philosophical system. This concerns theists and atheists, Catholics or, let us assume, satanists. Modern logic must be used in proofs of God’s existence as well as in other proofs. One should know that modern logic neither assumes nor implies any metaphysics, but if by using it one derives some philosophical consequences, this means that some extralogical theses have been presupposed. Declarations of this kind were provoked by interventions of various participants at the Congress who, speaking more or less precisely and responsibly, offered a couple of reservations concerning the possibility or necessity of applying logistic to philosophy. Different accents could be found in these statements. The standpoint that excessive precision and responsibility in inferences can damage philosophy […] was the exception. […] The [other] group declared that philosophy, in particular, metaphysics, has its scientific methods and that only these methods lead to proper results. On the other hand, according to this view, the application of mathematical logic, for example to metaphysics in a manner similar to that occurring in the special sciences, only simplifies and vulgarizes problems without producing proper solutions. The representatives of this standpoint almost never questioned the importance of mathematical logic (incidentally speaking, they seldom had a sufficient knowledge of it), but only denied its usefulness in investigating philosophical questions.Footnote 9

In the light of this report, the discussion during the meeting organized by Michalski was a mirror of a more general controversy concerning the nature of philosophy and its methods conducted at the Cracow Congress. It is very probable that Sobociński, in his report about the entire congress, also summarized standpoints concerning the application of modern logic to Thomism. On the other hand, very similar questions were also discussed by Polish, so to speak, secular philosophers. Thus, the Cracow Circle undertook methodological problems which were vital for all Polish philosophy.

The philosophical program of the Cracow Circle was based on the belief that mathematical logic strongly influenced the development of the philosophical sciences in Poland. Its achievements and methods began to be applied to various extra-logical problems. Mathematical logic taught Polish philosophers how to be precise in arguments and directed their attention to the importance of logical and semantic analysis in elaborating philosophical problems.

This general program had to be qualified somehow in order to be coherent with Catholicism as a religion. The Cracow Circle was entirely loyal to Catholic orthodoxy. In particular, theology was considered as a negative norm for philosophy. Thus, the philosophers of the Cracow Circle assumed that philosophy and Christian theology are necessarily coherent. This is evidence that the members of the Cracow Circle shared the basic views of Thomas Aquinas about the relation between philosophy and theology, although only Bocheński and Salamucha explicitly declared themselves as Thomists. A far-reaching optimism was another mark of the discussed project. The members of the Cracow Circle were convinced that reformed Catholic (scholastic) thought will outstrip all other philosophical currents.

The main features of the methodology recommended by the Cracow Circle can by summarized under the following points:

  1. (a)

    The Formulation and defence of the Catholic world-view requires application of all modern methods of thinking;

  2. (b)

    One must distinguish the formal elements of the theory from the proper content of its teaching;

  3. (c)

    Making the theory precise consists in changing and perfecting the formal conceptual apparatus without destroying any of the essential content given by tradition;

  4. (d)

    Improving the content means that the related research covers all domains of humans thought and takes them into account, including those that are neutral or even inimical to the Catholic standpoint.

According to the Cracow Circle, Catholic philosophical doctrine should be formalized and even axiomatized. This claim concerned mostly ontology considered as applied logic. The justification of this postulate was similar to that offered as in other circles recommending logic as a good method of philosophy. This logical way of doing philosophy introduces exactness, precision of form in arguments and makes it possible to eliminate ambiguities and various defects of clarity. Thanks to such prospects, the language of philosophy can be essentially improved. Similar benefits concern the quality of arguments. For instance, logic can contribute to far better formulations of arguments for the existence of God or ways of speaking about His attributes. Philosophy in this respect is similar to mathematics, where, by formalizing and axiomatizing suitable theories, we can speak about Non-Euclidean spaces, real numbers and infinite sets, objects regarded as transcending usual human standards and resources of conceivability. Thus, logic, according to this project, offers a way (or even the only way) to convert Thomism into a normal scientific philosophy. This idea concurred with the general philosophical tenets of the Lvov-Warsaw School, which very strongly influenced Bocheński and his colleagues.

An important place in the programme was attributed to its historical justification. In particular, Bocheński argued that Catholic philosophy always, or at least during its golden era that is in the Middle Ages, respected the highest standards of precision. In particular, Thomas Aquinas used the best logical devices available to him. According to Bocheński, Aquinas would have no reservations about mathematical logic. This was partly based on Łukasiewicz’s view that there is a visible continuity in formal logic from Aristotle to the twentieth century, though eventually with interruptions caused by the epistemological trend in philosophy. Bocheński returned to this problem after several years. He contrasted Mr. Paleo (a scholastic orthodox thinker), Mr. Neo (an anti-philosophical modern logician) and the Aristotelian (an enlightened philosophical logician who knows mathematical logic as well as history of logic and philosophy.Footnote 10 This last attitude should be adopted by contemporary Thomists if they actually want to continue the methodological strategy of their master. Salamucha formulated two criteria for assessing philosophical systems. One appeals to the range of their content, the other to basic methodological principles defining the status of their theses. Thus, we can distinguish (a) maximalism as regards the range of content and methodological minimalism (for example, Bergson), (b) minimalism as regards the range of content and methodological maximalism (for example, logical empiricism). Now we can and should look for (c) methodological maximalism combined with maximalism as regards the range of content. Thomism improved by mathematical logic is a candidate for such a philosophy.Footnote 11

Of course, it is much easier to propose a philosophical program than to realize it. Fortunately, in the case of of the Cracow Circle we do have concrete attempts to pursue these declared claims. Its members undertook several analyses in order to demonstrate that modernization of Catholic philosophy via logic is possible and useful. This can be illustrated by several examples; for instance, advanced formalizations of traditional cosmological proofs of God’s existence (Salamucha, Bocheński), Bocheński’s studies on analogy, Salamucha’s treatment of the concept of essence and the levels of abstraction (he abandoned the traditional Thomistic account of this problem), or Salamucha’s suggestions about how to formalize analogical concepts as typically ambiguous in the sense of the theory of logical types as exposed in Whitehead’s and Russell’s Principia Mathematica.Footnote 12 All these and other investigations were very original and novel, not only with respect to Neo-Scholasticism. They could open a new chapter in the history of Catholic philosophy. Hence, the question of how successful the project of the Cracow Circle was is reasonable and interesting.

Historically speaking, the Cracow Circle was active for a very short time only. World War II ended its history. Salamucha, who was the spiritus movens of this group (Bocheński always stressed this point), was killed in the Warsaw Uprising in 1944. Bocheński and Sobociński left Poland after 1945; in fact, the former received Swiss citizenship before 1939, but he frequently travelled to Poland to meet Polish logicians and philosophers. The latter never returned to Poland after the war, Bocheński did so in 1987 for the first time after 1945. Drewnowski was the only member of the Cracow Circle who remained in Poland, but his academic activities were considerably restricted. One could eventually speculate about a possible development of this group in more favourable historical circumstances, but it would be mostly counterfactual considerations. Although it is difficult to compare the Cracow Circle, in fact, a small group of four people with such philosophical communities as the Vienna Circle or the Lvov-Warsaw School, let me point out that both of the latter disappeared after 1945 and never reappeared in their pre-war form. Of course, both schools persisted through the published works of their particular and distinguished representatives, but not as collective enterprises. The fate of the Cracow Circle was similar to that of more powerful philosophical camps. Although Bocheński himself continued to work in the spirit of the Cracow Circle to the last days of his philosophical creativity and a few others (for instance, Ivo Thomas, Albert Menne or Weingartner) did similar things, these efforts remained on the margins of Neo-Scholasticism. Bocheński, Sobociński and Thomas even tried to reactivate the Cracow Circle but they soon gave up this idea. Since we cannot say anything definitive about what could happen, the only way is to look at what could have happened with the project of reforming Catholic philosophy by formal logic.

As far as I know, Bocheński was the only person who tried to explain why the philosophical proposal of the Cracow Circle was not successful on a larger scale. His diagnosis pointed out the main cause to be the negative attitude of most Catholic philosophers toward using logic in philosophy. Bocheński and other members of the Cracow Circle were perfectly conscious that traditional Catholic philosophers considered mathematical (or symbolic) logic as something very questionable. This was clear even before 1936, that is, the year in which the Cracow Circle was established.Footnote 13 For instance, Jacques Maritain, a very influential Catholic philosopher recommended traditional logic as entirely sufficient for doing philosophy. The attitude of most Thomists toward mathematical logic was decisively hostile or at best suspicious. Some Thomistic thinkers pointed out that mathematical logic leads to atheism (Russell was mentioned as a principal example, in Poland the same judgement concerned Kotarbiński and Leśniewski). In Poland, Rev. Augustyn Jakubisiak published a book in which he radically criticized the use of mathematical logic in philosophy, in particular the attempts undertaken in Polish philosophy.Footnote 14 Łukasiewicz replied in the same year (1936) and patiently corrected several misunderstandings.Footnote 15 Thus, the Cracow Circle arose as a response to this negative evaluation of philosophical importance of the new logic. It is even indicated by the title of the published proceeding of the meeting organized by Michalski: Catholic Thought in the Light of Modern Logic.

The discussions in Krakow were very heated. Bocheński, Drewnowski, Łukasiewicz and Salamucha defended logic as an instrument of philosophy. Michalski was sympathetic to this attitude. Father Józef Chechelski, Father Piotr Chojnacki, Father Józef Pastuszka and Father (one of Poland’s archbishops) Jan Stepa represented the conservative side and expressed more or less negative opinions about the usefulness of modern formal logic in philosophy. They accused mathematical logic of conventionalism, relativism, positivism, mechanizing thinking, ignoring content in favour of formalism, liquidating metaphysics, and repeated Maritain’s statement that there is no reason to go beyond traditional Aristotelian logic which suffices for all actual philosophical needs. The defenders argued that logic as such does not lead to any substantive philosophical view. They also argued that logic is neutral with respect to atheism and theism. Thus, the objection that logic annihilates metaphysics is completely unjustified. As far more particular issues were concerned, the friends of logic tried to explain that objections of relativism, conventionalism, ignoring content or leading to mechanicism in the account of thinking are all based on simple misunderstanding. Finally, they pointed out that Catholic philosophy should be modernized by logic and that (see also above) this tendency is consistent with the best tradition of scholasticism represented by Thomas Aquinas who was open to innovations.

Neither side of in this controversy convinced its opponents. The success of the Cracow Circle in 1936 consisted in publicly proclaiming its views and winning approval on the part of several leading Polish philosophers and logicians, particularly those grouped in the Lvov-Warsaw School; Łukasiewicz was an especially important person in supporting efforts of the Cracow Circle. However, given the aformentioned historical facts, this philosophical group ceased to exist in 1939. Nevertheless, the criticism of its style of doing Thomism appeared after 1945 as well. Even in Poland, where the tradition of logical philosophy was still very vital after the war, Thomists (in particular, those belonging to the Lublin School of so-called existential Thomism) issued several reservations against the logical analysis of philosophy.Footnote 16 The typical objections of Jakubisiak and others were frequently repeated (see above). It was said that although logic is useful as a device of analysis, one must be very careful with formalization and axiomatization, for the content of concepts exceeds formal tools. For instance, Salamucha’s proposal to consider analogical concepts as systematically ambiguous was rejected as entirely inconsistent with the traditional account of metaphysical abstraction as governed by special principles, elaborated by metaphysics but not by logic. Similarly, the existential Thomists argue that the Five Ways find their sufficient justification in metaphysics. Thus, metaphysics is prior to logic, contrary to Bocheński’s view that ontology is applied logic. Although one can argue that contemporary scholastic philosophers have a (little) more sympathy for modern logic, this only means, at least as far logic’s significance for philosophy is concerned, that they recovered the moderate position of the 1930s. Otherwise, logic is tolerated but not recommended as something important for philosophy.

Bocheński was very annoyed by the failure of the project of the Cracow Circle. This is clearly expressed by the following quotations:

I am reporting at one philosophical congress my discovery that logic is neither scholastic nor Aristotelian logic. Then, one young professor, a layman but from a Catholic university says: “As a priest and a Thomist you should know…”. I immediately reply: “Stop, please please, a philosopher never is an “ist”. If one wants, I am a Thomist in the sense that I accept the principal attitude of Thomas, but I have no intention to contribute to Thomism; strictly speaking, I dislike it.Footnote 17

This conversation (of Mr. Paleo, Mr. Neo and the Aristotelian; see above—J. W.) having become known in authoritative circles, the Aristotelian has been excluded from two Academies of which he was formerly a member, that of Tradition and that of Science. It was stated in the first that a man who dares to read Principia Mathematica instead of the Logique du Port Royal is evidently a madman; while the board of the other declared that an Aristotelian could no be longer be tolerated in the company of scholars who have proved once for all that all truth is relative, that of their own opinion was included.Footnote 18

I was greatly annoyed when I was working on my second textbook in logic. It was an introduction to mathematical logic. My church censor ordered me to cancel references to scholastic thought. He argued that it is beyond any suspicion that the Schoolmen had something similar to mathematical logic.Footnote 19

We wanted to convert teachers in the seminars for priests but it was to no avail.Footnote 20

We wanted to apply mathematical logic to traditional Christian problems considered by St. Thomas. However, we lost.Footnote 21

Irony and disappointment ring out explicitly in these statements. Bocheński considered the failure of the program of the Cracow Circle as the ruin of hopes for making Catholic philosophy rational or scientific. He considered the conservatism of Thomists as the main cause of this situation. As I already conjectured, it is very likely that the loss of the logically oriented reform of traditional scholastic thought directed Bocheński toward analytic philosophy as free of any pressure from the side of world-views.