Thought

Albert is well known both for his works in logic as well as for those in natural philosophy. His most important works in logic are the Perutilis logica (Very Useful Logic), the Quaestiones circa logicam (Questions on Logic), and his Sophismata. In addition, he wrote commentaries on the Ars vetus (Isagoge, Categories and On Interpretation) and on the Posterior Analytics. Albert’s works in natural philosophy include commentaries on the Physics, On the Soul, On the Heavens, On Generation and Corruption, On Sense and What is Sensed, and on the Meteorology. He also wrote commentaries on the Ethics and on the Economics. In addition, he commented on John of Holywood’s (Johannes de Sacrobosco) astronomical work De sphera (On the Sphere) and wrote some (short) mathematical treatises including the Tractatus proportionum (Treatise on Proportions), which was modeled on Thomas Bradwardine’s treatise De proportionibus velocitatum in motibus (On the Proportions of Velocities in Movements). None of Albert’s theological writings - if he wrote any - survive.

A long-standing characterization of Albert was that he was only a transmitter and not an original thinker. This characterization, however, now seems no longer tenable. It is certainly true that he often relied heavily on others. For example, his commentary on the Ethics is strongly influenced by Walter Burley’s commentary. But in natural philosophy as well as in logic, Albert made important contributions of his own.

The most important and influential of Albert’s logical works is his Perutilis logica. This work is not a commentary, but an independent treatise consisting of six related tracts on various topics in logic. The first tract defines the basic terminology to be used in the rest of the tracts, such as sign and intention, and also discusses the basic structure of propositions. It is followed by tracts on the properties of terms, on propositions, on inferences and topics, on fallacies and, lastly, on obligations and insolubles. An important source of inspiration for the Perutilis logica was Ockham’s Summa logicae, both for its structure and for part of its doctrinal contents, but Albert’s work is considered to be both more systematic and more comprehensive than Ockham’s and contains much that is not found in Ockham. Also closely related to the Perutilis logica is Buridan’s Summa logicae, but since the relative priority between Albert’s and Buridan’s work is still unclear, it is difficult to answer questions on influence and originality. It is still possible, however, to point out some interesting differences between Albert’s and Buridan’s views.

One of the key differences that have been noted is the different ways in which Albert and Buridan understand how the copula ‘‘is’’ (est) functions in a proposition. Buridan interprets it in a manner that makes it atemporal, in the sense that in a proposition such as ‘‘man is an animal’’ the copula ‘‘is’’ not only applies to all men that exist presently, but to all men in the past and in the future as well. Albert, on the other hand, strongly emphasizes that ‘‘is’’ always and only signifies the present tense, which implies that in the proposition ‘‘man is an animal,’’ the term ‘‘man’’ only stands for (in fourteenth-century terminology: supposits for) all men presently existing. As a consequence, Albert and Buridan give a rather different explanation for the reasons why scientific propositions are eternally true. Since the subject term of a scientific proposition in Albert’s view only stands for presently existing things, he cannot just claim that the eternal, or universal truth of such a proposition is accounted for by the fact that it is true of all of the particulars that the subject term stands for. For, in order to claim universal truth, all the particulars in the past and in the future would have to be taken into account as well. Albert quite elegantly evades this apparent problem by saying that in order for a scientific proposition to be eternally true, all that is required is that each and every time the proposition is thought of, or uttered, or written, it is true of all the particulars existing at that moment.

Just like his Perutilis logica, Albert’s Sophismata also shows an Oxford influence. Sophismata (sophisms) are sentences that give rise to difficulties in their interpretation, because of certain ambiguities or other characteristics. One of the tools Albert relies heavily on to solve such sophismata is a distinction between compounded and divided senses (sensus divisus and sensus compositus), in the sophisticated form into which it was developed by William of Heytesbury. This distinction enables one to take the scope of modal operators into account when analyzing the truth value of a proposition.

Albert’s works in natural philosophy are closely related to the works of John Buridan and Nicholas Oresme. This has led scholars to believe that there was a so-called Buridan school in Paris, of which Buridan was the teacher and Albert of Saxony, Nicholas Oresme, Marsilius of Inghen, and Themon Judaeus were the students. This, however, was not the case. The fact that Buridan belonged to the Picard nation of the university, whereas Albert belonged to the English-German nation, more or less rules out the possibility of a teacher - student relation in the strict sense, and the fact that it is known that Albert incepted under Albert of Bohemia (from his own nation) does the rest. The doctrinal interconnections, however, between these philosophers are many and undeniable, even if the precise relations between them are unknown. The recently suggested description of this group as ‘‘a small intellectual network of nearly contemporary masters of arts, who were familiar with each others’ work and at times responded to each other’’ seems much more accurate.

One of the interesting themes in Albert’s important commentary on the Physics is his analysis of projectile motion. This type of motion was problematic to analyze within an Aristotelian framework, because Aristotle had insisted that all local motion occurs by contact between a mover and the thing moved. What then, in the case of projectile motion, is the mover that remains in contact with the projectile? A traditional (Aristotelian) answer - though certainly not the only one - had been that the motive force is transferred by the original mover to the air, after which one part of air would pass on this force - with diminishing intensity - to the next part, so that there is always contact between the projectile and that part of the air which currently has the motive force. This solution, however, has a number of difficulties, not the least of which is that it is hard to see how motion can be a continuous process when the motive force is transferred from one (seemingly discrete) part of the air to the next. Albert gives a different explanation for this phenomenon, one that was also given by Buridan. According to Albert, the original mover (for instance the person throwing the projectile) transfers the motive force to the projectile itself. Because the moving force becomes a quality of the projectile, there is no longer any need for any other direct contact between a mover and the projectile. The name under which this moving force in the projectile became known and famous was impetus, but Albert still used the term virtus motiva.

The topic of impetus also sheds some more light on the relation between Albert’s and Buridan’s commentaries on the Physics. It has now been shown that Albert’s commentary was composed somewhere between Buridan’s third redaction and his final redaction ofhis commentary on the Physics. Part of the evidence for this is that the term impetus, which was not used by Albert, is only used in Buridan’s final redaction of his commentary. But more importantly, in his final redaction Buridan, at times, responds to Albert or takes over elements from his discussions.

There is more disagreement between Albert and Buridan on the ontological status of quantity. Albert sides with Ockham when he reduces the ontological category of quantity to the categories of substance and quality whereas Buridan had defended that quantity must be a distinct ontological category besides substance and quality. As a consequence, Albert considers condensation and rarefaction - the phenomena that had occasioned Buridan to assign a separate status to quantity - as merely forms of local motion of the parts of a given substance. Albert did not, however, always take Buridan’s Physics commentary as his starting point. On the questions of the possibility of the existence of a void, for example, he models his discussions on Oresme’s commentary instead.

Oresme’s works have also, again together with Buridan’s, influenced Albert’s commentary on Aristotle’s On the Heavens. But apart from the fact that Albert discusses many questions not found in either Buridan or Oresme, he also surprisingly and very interestingly organizes the material in a novel way. Instead of following the traditional division of On the Heavens into four books, he chooses to arrange the work according to the three major

Topics he distinguishes in Aristotle’s work: the world as a whole, its noble parts, namely heaven and earth, and its less noble parts, namely the elements, especially insofar as they exhibit the qualities of being either heavy or light. As a consequence, Albert treats the traditional books three and four as a thematic unity and writes a commentary that is divided in only three parts.

To sum up, not only was Albert thoroughly familiar with a wide range of philosophical views in his time, but he was also responsible for introducing several new ideas into the philosophical discussions. Albert was very influential and remained so for a long time, which can be demonstrated not only by the number of surviving manuscripts, but also by the number of times his works were printed. His commentaries on the Physics, On the Heavens, and On Generation and Corruption, as well as many of his logical works were all printed multiple times in the late fifteenth and early sixteenth centuries. His Tractatus proportionum was even printed at least 15 times. Albert thereby became one of the most important figures in the transmission of fourteenth-century philosophy.

See also:  > John Buridan > Marsilius of Inghen

> Nicholas Oresme > Thomas Bradwardine > William Heytesbury > William of Ockham