The heart of this assignment is the group of selections (pp. 3-5) from book I of Bacon’s Novum Organum (1620) and the contrasting views (pp. 10-14) from Descartes’ Discourse on Method (1637). The selections from Aristotle (pp. 1-3) are intended to provide background for Bacon, and the selections from Bacon’s book II (pp. 5-10) provide illustrations of the sort of methodology he has in mind.
Bacon and Descartes wrote near the beginning of the scientific revolution, and both reacted against the tradition inherited from Aristotle (though this is clearer in the selections from Bacon than in those from Descartes). Aristotle wrote nearly 2,000 years before them, but his conception of systematic knowledge had been revived around 1200 and had dominated thinking about science during the next four centuries.
Aristotle. Bacon’s title alludes to Aristotle’s Organon (or ‘instrument’), a label given to the first several works in the traditional ordering of the Aristotelian corpus. The three selections from Aristotle come from the Posterior Analytics, a work from the Organon which provides Aristotle’s general view of scientific knowledge.
• The first gives an example of scientific explanation and notes its asymmetry (X might explain Y without Y explaining X, an issue we will encounter again later in the course).
• The second points to the centrality of general laws in explanation. You can take the “commensurate universal” that he speaks of to be the broadest class all of whose members have the feature being explained. (E.g., “Why do dogs have a spinal chord?” “Because they’re vertebrates, and all vertebrates have spinal chords.”)
• The third selection concerns the way we come to grasp universals. Notice the role he gives to sense perception (and that he denies that this grasp is innate, that we are born with it).
Bacon takes Aristotle to claim that we jump quickly from sense perception to the highest universals and then work our way down to explain more specific generalizations and argues instead for a systematic gradual ascent.
• In describing the first of ways to truth he mentions in XIX, Bacon seems to have Aristotle’s method in mind, and the generalizations this first way leads to are what he calls “anticipations” (as opposed to “interpretations”) in XXVI (presumably since they might, in principle, precede any observation). Notice his repeated emphasis on the gradual move up from particular observations in his description of his own second way to truth.
• The selections from Bacon’s book II give an indication of how deliberate he takes this process to be. Bacon’s interest in the organization of research was given an explicitly bureaucratic form in his New Atlantis, and this vision of a research establishment working systematically to advance knowledge was influential in the next couple of centuries as the scientific revolution took hold. (William Harvey, who first recognized the role of the heart in the circulatory system and was at one time Bacon’s physician, is famously reported—by a younger contemporary, John Aubrey, in his Brief Lives—to have said that Bacon “writes philosophy like a Lord Chancelor,” citing an office that Bacon in fact held at the time he wrote the Novum Organum.)
Descartes’ work is a semi-autobiographical preface to three short scientific treatises.
• The first selection describes the method that he took to be responsible for his development of analytic geometry. Notice that, although he speaks in his third law (p. 10) of “ascending” from the simplest to the more complex, this will amount to a descent from the most general to the more specific.
• The beginning of the second selection makes this even clearer: he proposes to use his method to move from an understanding of fundamental physics to results applicable in medicine. And the role he gives to experiment is to guide the direction of this descent.
In part V of his Discourse, Descartes had sketched an account of
what would happen in a new world, if God were now to create somewhere in the imaginary spaces matter sufficient to compose one, and were to agitate variously and confusedly the different parts of this matter, so that there resulted a chaos as disordered as the poets ever feigned, and after that did nothing more than lend his ordinary concurrence to nature, and allow her to act in accordance with the laws which he had established
(His sketch included, incidentally, an extended presentation of his alternative to Harvey’s account of the circulatory system.) His use of the hypothetical “what would happen if” was partly designed to avoid attack by opponents of the new science; but, together with his discussion of experiment in part VI, it also points to a way of conducting science—namely, proposing hypothetical explanations on the basis of fundamental principles and using experiment to select among these proposals—and this method provides a sharp contrast to Bacon’s.