Alioto, Ch. 10: The Gate and the Key: Empiricism, Mathematics, and Experiment


Contrary to later (modern, especially positivist) accounts of the Middle Ages, Medieval science understood the role of observation, measurement, and experiment.

But the focus on the empirical raises a central problem - one we've seen since the Pythagoreans and Thales: given our use of abstract theoritical principles - most centrally, mathematics - in our accounts and explanations of the physical/material world - how are we to understand the relationship between the things known by mind (theory) and the things known through senses (the objects of our observation, measurement, and experiment)?
This question is dealt with most directly in the Middle Ages in the debate concerning the univerals. Robert Grosseteste provides an apparent philosophical solution - one that lays part of the metaphysical and epistemological foundations of the emerging philosophy/natural science.


Alioto notes that while Aristotelian science was studied largely "out of the textbook," so as to focus on an exegesis [interpretation] of the text, with a view towards discovering "...why things happened, their causes, and to find out what deductions could be made from accepted or inducted principles," -- there was also a second dimension to medieval science,

...vaguely similar to the lab part of our modern course. There was an emphasis upon observation, measurement, and even experiment. To be sure, it took a secondary seat to the study of the text, and its practitioners hardly got their hands dirty. It did, however, stress the procedures we would equate with the lab. (135)

"This method was called by Albert the Great the "Pythagorean" approach. It certainly had many ancestors besides Pythagoras, and we may simply call it the practical quantitative tradition of measurement." (136)

Examples:

Astronomical/astrological observatories, "in which it was more important to insure the accuracy of tables than to speculate upon the reality of the spheres."

"The Hermetic tradition, although fragmentary in the Middle Ages, gave rise to the alchemist's laboratory where experiments were conducted based upon the texts."

"the Archimedean geometrical tradition in statics"

"the importance of weights and measures" -- increasing with developing commercial interests of the later Middle Ages

"In optics the mathematical treatment of light rays and theories of vision were combined with Aristotle and the medical tradition of Galen."

Most importantly -- "In a basically agricultural society such as Medieval Europe," the application of Euclidian geometry in surveying. (136)

Euclid also applicable to the geometrical analyses of optics and astronomy.

A middle ground emerges here. Both Euclid and Aristotle were taken as "the best illustrations of true scientific methodology. The actual application of geometry to natural phenomena represented a kind of intermediate science, falling between the rigorous demonstrations of pure mathematics [Euclid, Elements] and the logical deductive causality of natural philosophy [Aristotle, Posterior Analytics]." ([emphasis added, C.E.]: 136)

Leonardo Fibonacci of Pisa as taking up this "intermediate science." [1220: The Application of Geometry]

A merchant concerned with commerce: encountered Arabic numeration and algebra. His "Liber abbaci popularized algorism (arithmetic founded upon Arabic notation) which had attracted little attention inside the schools. We hear Roger Bacon admonishing theologians to study the system in order to better acquaint themselves with the art of numbering." (136f.)

STATICS (in medieval terms, the science of weights)

Again, its practical applications would seem to lie in areas of commerce. There was, however, a theoretical tradition, derived from a pseudo-Aristotelian work (possibly done by Strato) called Mechanical Problems, as well as from the methods of Archimedes received through the Arabs. The most significant contribution of the medievalists was to combine these two traditions. ([emphasis added, C.E.]: 137]

See description of Jordanus, p. 137 -- all of which serves as an example of "some application of mathematics to natural phenomena."


The Problematic: the relationship between mathematics and natural phenomena

Alioto points out that a "methodological problem" exists regarding any effort to apply mathematics to natural phenomena [a problem illustrated most forcefully by Plato and his arguments for the primary reality of the Forms]. Alioto gets to this with an example from Euclid:

Recall the Euclidian method of deduction from axioms and common notions. One of the latter states that things which coincide are equal. Thus Euclid proved that two triangles were congruent by placing one upon the other and showing that the given angles must coincide. This may seem perfectly self-evident on paper using perfect triangles. But may we say that in the physical world the universal triangle remains uncorrupted through the act of movement? In fact, we might easily contend that mathematical definitions tell us nothing about their actual existence in the physical world. Where, then, do the principles of mathematics come from?

[Recall here, however, that Plato develops the doctrine of the Forms precisely in order to justify and ground mathematical knowledge. Again, look at the notes, on "Plato and the Development of Science," I.E.2.]

We might attempt to escape the question of the relationship between mathematical definitions and relations, on the one hand, and particular phenomena observed through the senses, on the other, -- formulated here in an especially Platonic framework -- by taking an Aristotelian approach: on such an approach, remember, we would say that the forms or the universals are somehow in particular things in some sort of form/matter combination. This approach, however, also runs into a roadblock:

And if universals are immanent in things, as Aristotle said, how can we actually maintain that universals are in any way different from their singulars. The unity of a universal, a triangle, is in all triangles; yet, even if we can show this universal for every triangle, we still have the problem of unity in diversity. There still exists a logical hiatus between the universal or formal definition and the thing which is actually observed or measured -- between the lecture and the lab. (138)

That is, if Plato emphasizes the difference between perfect, unitary, universal Forms knowable by the mind and sense phenomena as imperfect manifestations or reflections of these Forms --

Aristotle so far collapses the difference between the two, so that it becomes difficult to "see" how the universal or form (as the underlying unity knowable by the mind) is sufficiently distinct from diverse, particular objects of sense-knowledge.

Somewhat in the way we saw with Anaxagoras and his "seeds" -- to say that things are what they are because they are what they are (i.e., hair is hair because hair "seeds" predominate in it [Anaxagoras]; or, a "chair" is a chair because it contains the form chair [Aristotle]) seems unsatisfactory as an explanation. In logical terms, it is simply circular. In terms of the structure of explanation we seem to be interested in since at least the PreSocratics, if not in mythopoetry itself -- there is no simplifying structure of explanation which accounts for the diversity of many different changing things in the world of sense by tracing it to a unitary, underlying set of causes or forces (e.g., water, aer, the unlimited, the Good, etc.)

This methodological problem receives an apparent resolution in the work of Robert Grosseteste (1168-1253) [FRANCISCAN]

Defines scientific knowledge as the definition or discovery of the universal -- which could be grasped apart from divine illumination [contra Augustine!]

Only before the fall was the human mind able to grasp in one act both the essence and singular. In the corrupted material world, knowledge had to begin with the senses, and scientific knowledge could be achieved only through demonstration, whose instrument was the syllogism. (138)

[Note: as his name suggests, this is an English thinker: this orientation towards sense-knowledge as the basis of knowledge not only points backwards towards Aristotle, but also forward to Anglo-American empiricism as a traditional/cultural assumption about what constitutes knowledge.]

Roughly, what Grosseteste comes to in the problem of the universals is to attempt a middle ground between Plato and Aristotle.

In the Aristotelian direction, he argues that we somehow move from an inspection of various geometrical figures (called "resolution") to a process of reconstituting "...these qualities theoretically in our minds," so as to arrive [how?] at the definition -- for example, of a right-angled triangle. And, as with Aristotle, Grosseteste insists that this universal definition or premise in fact exists in real things as their form and cause. "But [in the Platonic direction] the universal is neither one triangle nor many; rather it seems to be a logical entity outside the corporeal world!" (138f.)

Even so, because such universal definitions, propositions, claims, etc. are only "suggested" in this reconstitution process -- they fall short of attaining the status of ultimate reality ascribed to the Forms by Plato.

And it is just this ontological status of the universals [neither "purely" Aristotelian nor "purely" Platonic] that not only serves as a justification of the relevance of mathematics to sense-world phenomena: it further serves as a metaphysical justification of the need to experiment in the development of scientific knowledge.

So Alioto notes:

...the premises gained through induction...are only hypotheses when they are generalized into a universal statement about all right triangles. As hypotheses, they can be doubted. A hypothesis is for Grosseteste simply a formal assumption of our expectation. In order to convert our hypothesis into a scientific demonstration which reveals the actual state of its existence we must go out and experiment....

Experiment seemed to mean for Grosseteste what it means for us: a controlled procedure designed to verify or falsify a hypothesis. In effect, it is a test of our definition, coming after induction. In fact we may deduce actual consequences not included in the original generalization. Through experiment and observation we may distinguish the true causes from the possible, grounding our demonstration in the factual world. (139)

And, just as mathematics is justified as a mode of knowing the material world by a change in the metaphysical or ontological status of the universals -- so it is further justified through a metaphysical conception of the universe: "...the actual structure of the universe was generated by a self-diffusion of light (lux)....the primordial cause of all natural effects. And Grosseteste explicitly held that such causes must be expressed by lines, angles, and figures." (139)