In April 1518 Martin Luther was called upon by the Augustinian order of Germany to set out and defend his theology at the General Chapter of Heidelberg. While Luther was rather thoroughly surrounded by controversy he would be presenting the theological ideas which had produced this controversy to those who shared much of his Augustinian thinking. The name of the presentation Luther delivered is the Heidelberg Disputation. The Heidelberg Disputation consists of a number of theses divided between philosophical theses and theological theses. The theological theses are explained in much greater detail than are the philosophical theses. Luther actually overlooks further explanation of his philosophical theses and chooses instead to let them stand on their own whereas after initially stating his theological theses he returns to them in order to further explicate and defend them. Perhaps this is a reason that the philosophical theses are largely overlooked in literature written on Luther. It may also be that theologians do not want to interact with strictly philosophical concepts in Luther and by extension Aristotle or that the philosophers who would perhaps be better suited to address Luther’s understanding of Aristotle are simply not generally interested in Luther as a philosopher. Whatever the reason is for the relative silence regarding Luther’s philosophical theses in his Heidelberg Disputation it is evident that Luther’s theology and philosophy are inextricably connected to one another so that a deeper understanding of Luther’s philosophical theses lends greater insight into Luther’s theology and vice versa.
The Heidelberg Disputation is of utmost importance “for understanding Luther’s developed theology.”
Here he not only expanded his theology of sin, grace, and free will, but also offered his own positive theological agenda centered in the “theology of the cross” (theologia crucis). In this formulation of theological method we begin to hear Luther’s distinctive contribution.
Sin, grace, and free will had everything to do with Luther’s theses on philosophy because he found the traditional use and abuse of Aristotle by the Catholic Church to be every bit as mistaken as the theology of the Catholic Church in general and for the same reasons.
Luther had come to think that the trouble with the whole tradition that had developed from Thomas Aquinas was that it tended to be dominated by its opening theological moves. Since the existence of God could be shown rationally or philosophically a style of theology developed that moved too smoothly from what could be known and comprehended clearly in creation to the grace of God in Jesus Christ. Though Thomas himself was clear that the saving mysteries could not be known by reason, much of the energy of subsequent theology went into these foundational questions.
Sin has such far reaching consequences that the intellect of humanity is affected by it and hence is not trustworthy when utilized apart from the revelation of God. Grace is necessary not only for salvation but also to free the mind from its mistaken philosophical wanderings. Salvation does not come through human reasoning by way of philosophy operating in accord with itself or in accord with unaided and unregenerate human thought. Luther thus went after those places where the faulty and incomplete views on sin, grace, and free will held by the Catholic Church had resulted in faulty philosophy as well. The Catholic Church was essentially basing their theology upon pagan philosophy. Luther believed this to be a completely backward approach and insisted upon having his theology of the cross as the lens through which both philosophy and theology may be correctly understood and used. To do otherwise is to contradict Scripture.
The theologians of Martin Luther’s day were infatuated with imposing unbiblical ideas upon the doctrine of God and the Bible through secular philosophy.
This could obscure what St. Paul had taught so forcefully: the cross of Christ is not a concept compatible with human wisdom and philosophy, but only with deep folly and offense. The cross is not inspiring but a scandal. Therefore the true theologian is not the one who argues from visible and evident things (following Aristotle), but rather the one who has learned from the cross that the ways of God are hidden (des absconditus), even in the revelation of Jesus Christ.
The Heidelberg Disputation is rather well developed with Luther elaborating upon his philosophy and theology by drawing out conclusions from Scripture and showing how the views of different theologians relate to one another and also his own view.
What emerges in this document is Luther’s radically grace-centered theology that sets the righteousness of God not only against the claims of philosophy for wisdom, but also against all the best moral achievement of humanity. It is an appeal to rediscover the sharp voice of Augustine (especially in his controversy with Pelagius), which apparently had become muted even in the Augustinian order.
Of course, Augustine was hardly Luther’s only resource in theological controversy. The words and works of Luther are saturated with biblical thought and he no doubt had passages of Scripture in mind even while writing out his theses concerning philosophy.
In 1 Corinthians 1.18-25 the Apostle Paul writes concerning the Gospel or “word of the cross.” It will be shown that Luther alludes to this passage during the course of presenting his philosophical theses when he speaks of becoming “thoroughly foolish in Christ.” The word of the cross which is the Gospel is not perceived as being wise or even reasonable by those who reject it. Those who have received the word of the cross view it as being the power of God and are being saved by it. It is likely that their being saved by the word of the cross is one of the reasons they do view the cross as the power of God. Meanwhile, those who are not being saved but are perishing count the word of the cross as folly. They consider it foolishness rather than power or wisdom and consider themselves to be wise even in their proclamation that the cross is foolish.
Paul quotes from the Old Testament that God will destroy the “wisdom of the wise.” In Paul’s context the “wise” at least includes the Greeks. Aristotle, whom Luther is writing about in his philosophical theses, is thus numbered among the wise of Paul’s passage. In verse 20 Paul asks rhetorically, “Where is the one who is wise? Where is the scribe? Where is the debater of this age? Has not God made foolish the wisdom of the world?” In verse 21 Paul appeals to the wise counsel of God as ultimately behind the placement of human reason in God’s redemptive plan. It is not possible for someone to come to know God through wisdom. Wisdom might be taken to refer more specifically to human wisdom, reasoning, or philosophy. God has determined that the world will not know Him through wisdom. Perhaps the reason for this is the weakness of humanity’s reasoning, the arrogance which often accompanies human wisdom, the uneven inclinations people have toward philosophical understanding, or something else along these lines. Not surprisingly Luther appeared to ground the folly of using reasoning as a path to God in the inability of humanity resulting from sin. The verse does not give a reason for God’s having determined that human wisdom would have the place that it does in His redemptive plan. What the passage does state is that it was wise of God to make things this way. It is “in the wisdom of God” that the world “did not know God through wisdom.”
Paul goes on in verse 21 to explain that while wisdom is not a route to the knowledge of God foolishness is for “it pleased God through the folly of what we preach to save those who believe.” Paul is following verse 18 and presenting his case from the perspective of those who are perishing and believe that the “word of the cross is folly.” Paul and the Apostles preached what is considered folly, not wisdom, because they preached the Gospel message which is the word of the cross. God is nevertheless pleased in saving those who believe this message that is considered foolishness by the standards of even the wisest reprobate.
Verses 22 and 23 describe Greeks or Gentiles as seeking wisdom but finding the preaching of Christ crucified to be folly. What is true for the Greek of Paul’s time is no less true for the earlier Aristotle or any other number of other people for whom the message of the cross is foolishness as compared to the human wisdom some attempt to use in order to come to know God. All people come to the saving knowledge of God not through the means of human wisdom, but through belief in the Gospel. In verse 18 those who see the word of the cross as the power of God are those who are being saved, in verse 21 those who are being saved are those who believe the word of the cross, and in verse 24 those who see Christ as the power and wisdom of God are those who are called from both the Jews and the Greeks. The difference between those who see the cross as foolishness and those who see it as power and wisdom is that the latter are saved while the former are not. The reason that some are saved while others are not is because the saved have believed on Christ. The reason that some Greeks believe while others do not is not because of wisdom, but because of God’s call based in His gracious election. People are ultimately saved not because they are wiser than others, but because they are chosen by God. (1 Corinthians 1.27) Hence the route to the knowledge of God according to the Bible is by grace through faith. (Ephesians 2.8)
In his 29th thesis Luther writes that, “He who wishes to philosophize by using Aristotle without danger to his soul must first become thoroughly foolish in Christ.” In this statement Luther does not dismiss philosophy as such or even Aristotelian philosophy but rather makes a qualification for its use. Failure to qualify the use of Aristotelian philosophy in the way Luther suggests results in danger to one’s soul. In order to both use Aristotelian philosophy and avoid danger to the soul one must “become thoroughly foolish in Christ.” It seems that Luther is here alluding to 1 Corinthians 1.18-25. The prerequisite to using Aristotelian philosophy is becoming foolish in Christ. The interpretation is that while Aristotelian philosophy will not deliver one’s soul it is still useful. Becoming foolish in Christ is having faith in Jesus. Interpreted in slightly broader terms faith in Christ Jesus precedes a right use of reason. This broader interpretation is warranted given the nature of the philosophical theses in the Heidelberg Disputation, the context of Luther’s other works, and the arbitrariness which would be entailed by suggesting that Luther rejected Aristotle alone or thought that other philosophers could be used without danger to the soul and without faith in Christ. While Luther emphasizes the foolishness of following Christ he also points out problems in Aristotle’s philosophy and if nothing else establishes that Aristotle’s philosophy is inconsistent with Scripture. Luther highlights that God has destroyed the wisdom of the wise as exemplified in Aristotle.
Luther continues his philosophical theses by stating in his 30th thesis that, “Just as a person does not use the evil of passion well unless he is a married man, so no person philosophizes well unless he is a fool, that is, a Christian.” That “becoming foolish in Christ” is properly understood as exercising “faith in Christ Jesus” as mentioned earlier is confirmed by the thirtieth thesis in that Luther states that his use of “fool” is synonymous with “Christian”. Here Luther uses an analogy of a married man. The analogy pertains to the use of philosophy.
Conceivably there are many things that a married man is able to “use” well that an unmarried man is not able to use well. Luther provides the example of the “evil of passion.” That philosophy in general is in view is clear in this thesis and confirms the conclusions drawn from the previous thesis. In order to philosophize well or in order to be a good philosopher one must be a fool which Luther here explains is a Christian. Luther’s use of “fool” mimics the Bible, but it also matches Luther’s tendency to revel in paradox and antithesis. Luther is implying that the fool is wise. It is not just that one cannot use philosophy without danger to the soul without being a Christian, but it is also that the Christian actually uses philosophy better and does so through faith. Presumably faith is the lens through which everything else must be viewed. To put it another way; faith precedes reason and gives way to its rightful use. Philosophical reasoning which is predicated upon faith is something which is useful, does not damn the soul, and can be done well. Over against this the person without faith will find philosophy useless (even if he or she is not cognizant of this fact), damning, and poorly done. These contentions match quite well with the testimony of the passage provided above. Luther is likely attempting to argue from what he has read before in the Bible concerning the philosophical wisdom of the world.
Luther does not argue for his assertions philosophically but he has no need to. If philosophical theses are inconsistent with what Scripture has to say concerning philosophy then they are to be rejected. Luther is showing that traditional philosophical theses accepted by the Catholic Church as a part of tradition are at the very least in many cases inconsistent with the teaching of Scripture. Luther provides a number of examples in Aristotle. Luther writes, “It was easy for Aristotle to believe that the world was eternal since he believed that the human soul was mortal.” In this 31st thesis Luther moves on to argue against specific allegedly Aristotelian ideas and starts with Aristotle’s belief that the world was eternal. Luther contends that it was “easy” for Aristotle to believe that the world is eternal. The human soul, by contrast, is mortal. Whatever else this means; Luther is highlighting that Aristotle’s understanding of the world as eternal is in some way consistent with Aristotle’s position that the soul is mortal. For Luther, both the proposition that the world is eternal and the proposition that the soul is mortal are false. Christian theology would have it that the world was created and so is not eternal and that the soul will go on after death. Luther at the very least argues that Aristotle’s views on the nature of the soul and world, while possibly consistent with one another, are nevertheless inconsistent with Christian theology.
Luther next calls the implications of Aristotle’s theory of forms into question in the 32nd thesis. In Aristotle’s theory there are material forms. Luther points out that if the number of material forms is the same as the number of created things then it follows that all created things are material. Following Luther; accepting Aristotle’s theory of the forms appears to lead to accepting that all created entities are material entities. If this is correct then it is certainly inconsistent with particular tenets of Christianity. Luther also mentions that, “Nothing in the world becomes something of necessity; nevertheless, that which comes forth from matter, again by necessity, comes into being according to nature” before moving on to another important point in Aristotle.
In his 34th thesis Luther writes, “If Aristotle would have recognized the absolute power of God, he would accordingly have maintained that it was impossible for matter to exist of itself alone.” It is important to realize that Luther did not believe that Aristotle had come to recognize the absolute power of God. This fact points again to the inability of humanity to come to a saving knowledge of God by way of pagan, faithless philosophy. If Aristotle himself did not make it to the God of the Bible then how can one following Aristotle without first placing his or her faith in Christ ever hope to reach the God of the Bible in his or her own conclusions? Aristotle maintained that matter actually existed of itself alone. The material world had always existed. If it is actually the case that matter has always existed then it is obviously possible that matter has always existed of itself alone. Luther points out that Aristotle’s view that it is possible for matter to exist of itself alone is actually inconsistent with a Christian view. Once the absolute power of God is recognized one cannot continue to hold as Aristotle did that it is possible for matter to exist of itself alone. The world in Aristotle’s view is self-existent while in Christianity only God is self-existent. God alone has always existed and does not depend upon the world in any way. Thus to ascribe eternality to the world is to attempt to attribute to the world characteristics that God alone possesses. Luther continues to find fault with Aristotle in his 35th thesis where he writes, “According to Aristotle, nothing is infinite with respect to action, yet with respect to power and matter, as many things as have been created are infinite” and in his 40th thesis which states that, “To Aristotle, privation, matter, form, movable, immovable, impulse, power, etc. seem to be the same.” Interestingly, Luther gives credit to other philosophers and criticizes Aristotle for having found fault with them. Thus in the 38th thesis Luther pits Aristotle against the pre-Socratic philosopher Parmenides and claims that the “disputation of Aristotle lashes out at Parmenides’ idea of oneness (if a Christian will pardon this) in a battle of air.” Luther takes another swipe at Aristotle in his 39th thesis by criticizing him for not thinking that Anaxagoras was the “best of the philosophers” if it was in fact the case that “Anaxagoras posited infinity as to form.”
Luther contends in his 36th thesis that “Aristotle wrongly finds fault with and derides the ideas of Plato, which actually are better than his own.” Here Luther not only criticizes Aristotle, but praises Plato. He does so again in the 37th thesis not by first criticizing Aristotle, but by praising the Pythagoreans. The Pythagoreans who developed mathematics and held to the principles of mathematics as making up matter itself (“mathematical order of material things”) are said to have “ingeniously maintained” their philosophy. Obviously Luther was not a stranger to ancient Greek philosophy. He recognized the cleverness of the Pythagorean philosophy and gave Pythagoras credit for it but only as a precursor to exalting Plato’s doctrine of the interaction of ideas as being “more ingenious” than the observations of Pythagoras. In praising Plato in this way Luther implicitly reaffirms the more Platonic teachings of Augustine over against the more Aristotelian teachings of Thomas Aquinas while in the midst of his fellow Augustinians.
Luther’s theology is not wholly separate from his philosophy, and it may be argued that the two are very closely related to each other. Luther views philosophy through his theologia crucis. Parallel to the reasoning of humanity are the works of humanity which Luther explicitly addresses in his theological theses. It is not out of line with Luther’s contention in his theses to take his words pertaining to human ability to be just as applicable to reason as they are to other human works. Luther’s statement that “he who acts simply in accordance with his ability and believes that he is thereby doing something good does not seem worthless to himself, nor does he despair of his own strength” may be modified by replacing “strength” with “reason” without complaint from Luther. Some indeed “strive for grace in reliance on” their own reasoning. That this is not an unjustified move is confirmed by the 19th thesis where Luther writes, “That person does not deserve to be called a theologian who looks upon the invisible things of God as though they were clearly perceptible in those things which have actually happened [Rom. 1:20].” Here Luther is explicitly addressing what he also addresses in his philosophical theses. Luther believes that recognizing the invisible things of God does not make one “wise” as Paul still calls the “theologians” of Romans 1.22 “fools”. Heino O. Kadai comments on this 19th thesis.
The “invisible things of God,” His eternal power and deity, cannot be properly derived from a knowledge of things. Luther clearly rejects the Thomistic type of natural theology. But he does not reject a “natural” knowledge of God. As far as Luther is concerned, to move from below to above, from creation to the Creator via analogia entis is not sound theology.
Instead, the person who is to be called a theologian “comprehends the visible and manifest things of God seen through suffering and the cross.” Again the folly of the cross is set in opposition to the wisdom of the world. Kadai explains, “Here a contrast is established between the invisible nature of God and His majestic attributes (see Rom. 1:20) on the one hand, and His visible back side of humanity, weakness, and foolishness (1 Cor. 1:25) on the other.”
Further contrast emerges between knowledge of God from His works and from His suffering. A true theologian seeks God were God Himself has hidden His revelation: in the foolishness, humility, and shame of the cross.
Luther continues to develop this insight in his commentary on the 20th theological thesis.
Luther understands 1 Corinthians 1.25 to teach that where humans misused their knowledge of God that they had through works, God provided knowledge of Himself through suffering, and this is how God has destroyed the wisdom of the wise. People must come to know God on His own terms and this is why one must become foolish in Christ prior to using Aristotle properly without danger to the soul. According to Luther, “it is not sufficient for anyone, and it does him no good to recognize God in his glory and majesty, unless he recognizes him in the humility and shame of the cross.” One will not reach God through his or her own ability to reason as, “true theology and recognition of God are in the crucified Christ, as it is also stated in John 10 [John 14.6]: ‘No one comes to the Father, but by me.” The attempt on the part of those who would endorse the philosophy of Aristotle as the means of knowledge of God to know God on their own should be contrasted with the knowledge of God which God has already made available.
Using his reasoning power man may seek to know God by way of philosophical reflection or contemplation of created reality. In such cases the goal is the knowledge of God as He is in His naked majesty. Luther knew that such a quest was doomed to failure. Man simply cannot bear exposure to the glory of divine majesty.
God has made Himself available to know through Christ Jesus. Where the “theologians of glory” were seeking knowledge of God through their own works and their own secularized philosophical thinking Luther turned to Scripture and warned that God had made Himself known in Jesus Christ. Knowledge of God is obtained by way of what God has done, and God uses that which the world deems folly to make Himself known. In his 22nd thesis Luther argues that the love of wisdom comes as a result of not knowing yet hating the cross and that the desire for knowledge is only encouraged by the acquisition or pursuit of wisdom but is not satisfied by it. The desire to become wise must be put away if one is to know true wisdom.
In other words, he who wishes to become wise does not seek wisdom by progressing toward it but becomes a fool by retrogressing into seeking folly. Likewise he who wishes to have much power, honor, pleasure, satisfaction in all things must flee rather than seek power, honor, pleasure, and satisfaction in all things. This is the wisdom which is folly to the world.
It is clear just from a brief look at the philosophical theses of the Heidelberg Disputation that Luther did not wholly dismiss reason from theology. Luther’s view of the relationship between reason and faith is quite complex and addressing it ranges well beyond a discussion on the philosophical theses. Bernhard Lohse notes that Luther “could speak very harshly of the arbitrariness of human reason over against revelation.”
Nevertheless, all his theological work reflects an established as well as extensively developed view of reason and its application, so that it will not do simply to emphasize the contrast between reason and revelation. Further, on the basis of Luther’s statements it is necessary to distinguish reason’s tasks within the scientific sphere and the sphere of temporal authority, and reason in view of the relation to God.
Just the brief look at Luther’s philosophical theses show that while he is extremely critical of Aristotle and philosophy in general he also leaves room for them to be used once one has become completely foolish in Christ, as “The service of the ratio is indispensable and necessary, but the danger of overstepping its bounds is always present.” What Luther wants to prevent is giving in to the temptation to set reason up as dealing “autocratically with God’s Word.” Lohse nicely summarizes Luther’s view.
According to Luther, not only in the person prior to the revelation but in the Christian as well the ratio is continually in danger of becoming autocratic and of wanting to judge God’s activity according to its own criteria. This made it impossible for him to describe the spheres of ratio and revelation as merely supplementing each other. His ambivalence concerning a possible natural knowledge of God or its impossibility ruled out the notion that the ratio can as it were develop ideas regarding the doctrine of God that could serve as basis for ideas derived from revelation. Nor can the spheres of ratio and revelation be set in mere opposition to each other. The danger of the ratio’s autocracy exists prior to as well as following revelation.
In the end a discussion of reason in Luther is perhaps somewhat beside the point when it comes to the philosophical theses. What Luther is after in both his philosophical theses and his corresponding theological theses in the Heidelberg Disputation is the necessity of avoiding a theology of glory and striving instead to be a theologian of the cross.
 Martin Luther. “Heidelberg Disputation (1518),” in Martin Luther’s Basic Theological Writings: Second Edition. ed. Timothy F. Lull. (Minneapolis, MN: Fortress Press, 2005), 47.
 Ibid. 47.
 Ibid. 47.
 Ibid. 47.
 Ibid. 47.
 Ibid. 47.
 Ibid. 47.
 Ibid. 49.
 Ibid. 49.
 Ibid. 49.
 Ibid. 49.
 Ibid. 49.
 Ibid. 49.
 Ibid. 50.
 Ibid. 50.
 Ibid. 50.
 Ibid. 50.
 Ibid. 57.
 Ibid. 57.
 Ibid. 57.
 Ibid. 57.
 Heino O Kadai. “Luther’s Theology of the Cross,” in Accents In Luther’s Theology: Essays in Commemoration of the 450th Anniversary of the Reformation. ed. Heino O. Kadai. (St. Louis, MO: Concordia, 1967), 241.
 Luther, Heidelberg, 57.
 Kadai, Accents, 241-242.
 Luther, Heidelberg, 57.
 Ibid. 57.
 Ibid. 57.
 Kadai, Accents, 240.
 Ibid. 240-241.
 Luther, Heidelberg, 58.
 Ibid. 58.
 Bernhard Lohse. Martin Luther’s Theology: Its Historical and Systematic Development. ed. Roy A. Harrisville. (Minneapolis, MN: Fortress Press, 1999), 196.
 Ibid. 196.
 Ibid. 204-205.
 Ibid. 204.
 Ibid. 203.