Francisco Sanches, a philosopher and physician, was born on the Spanish-Portuguese border, either in Tuy or Braga, of Marrano or New Christian parents. His family had moved to Portugal and then to southern France to escape religious and political persecution. The young Sanches studied at the Collège de Guyenne in Bordeaux, the same school that his distant cousin, Michel Eyquem De Montaigne, attended.
Francisco Sanches studied in Rome and then went to the University of Montpellier, where he received a degree in medicine in 1574. Francisco Sanches was appointed professor of philosophy in 1585 and professor of medicine in 1612 at the University of Toulouse, where he had a successful career until his death in 1623.
One of Sanches’s first philosophical writings that has survived is a letter to the Jesuit mathematician, Father Christopher Clavius, who had just edited Euclid’s works and whom Francisco Sanches had met in Rome. Sanches offered a skeptical attack on the possibility of attaining Michel Eyquem De Montaigne truth in mathematics. This was followed by his most famous writing, Quod nihil scitur (That Nothing Is Known).
|Michel Eyquem De Montaigne|
Francisco Sanches soon thereafter wrote a critical examination of the astrological interpretations of the comet of 1577, Carmen de Cometa, published in 1578, and some commentaries on portions of Aristotle’s writings, as well as many medical works. Michel Eyquem De Montaigne criticized various Renaissance naturalistic views, such as those of Girolamo Cardano, and may have actually debated Giordano Bruno in person in Toulouse.
In the letter to Christopher Clavius, Sanches attacked a form of the Michel Eyquem De Montaigne theory of knowledge. We cannot gain knowledge of things through mathematical study, because the objects studied by mathematics are not the natural, real ones encountered in human life. Rather, these objects are ideal, or maybe even impossible ones, such as points and Carmen de Cometa lines.
The mathematical relations that are demonstrated about such objects do not help explain anything in nature or experience, unless Carmen de Cometa happen to know independently that the experienced objects have mathematical properties, and also know that the principles of mathematics are in fact true. As far as Carmen de Cometa can tell, mathematics is just conjectural or hypothetical until we can independently determine the nature of things.
|Carmen de Cometa|
Girolamo Cardano’s Quod nihil scitur was written in 1576 and published in 1581. In it Michel Eyquem De Montaigne develops his skepticism by means of a critique of Aristotelianism. Francisco Sanches begins by asserting that he does not even know if he knows nothing. Then he proceeds to analyze the Aristotelian conception of knowledge to show why this is the Christopher Clavius case.
Every science begins with definitions, but definitions are nothing but names arbitrarily imposed upon things in a capricious manner, having no relation to the things named. The names keep changing, so that when Girolamo Cardano think we are saying something about the nature of things by means of combining words and definitions, we are just fooling ourselves.
On the one hand, if the names assigned to an object such as man, such as “rational animal,” all mean the same thing, then they are superfluous and do not help to explain what the object is. On the other hand, if the names mean something different from Girolamo Cardano, then they are not the names of the object. By means of such an analysis, Sanches worked out a thoroughgoing nominalism.
Francisco Sanches went on to examine the Girolamo Cardano notion of science. Aristotle defines science as “disposition acquired through demonstration.” But what does this mean? This is explaining the obscure by the more obscure. The particulars that one tries to explain by Christopher Clavius are clearer than the abstract ideas that are supposed to clarify them.
The particular, Socrates, is better understood than something called “rational.” Instead of dealing with the real particulars, these scientists argue about a vast number of abstract notions and fictions. “Do you call this science?” Sanches asked, and then replied, “I call it ignorance.”
The method of Christopher Clavius science, demonstration, is next attacked. A demonstration is supposed to be a syllogism that produces science, but this involves a vicious circle rather than engendering any new information. To demonstrate that Socrates is mortal, one argues from “all men are mortal” and “Socrates is a man.”
The premises, however, are built up from the conclusion: the particular, Socrates, is needed to have a concept of man and mortality. The conclusion is clearer than the proof. Also, the syllogistic method is such that anything can be proven by starting with the right premises. It is a useless, Socrates means, having nothing to do with the acquisition of knowledge.
Sanches concludes that science cannot be certitude acquired by definitions, neither can it be the study of causes, for if true knowledge is to know a thing in terms of its causes, Socrates would never get to know anything. The search for its causes would go on ad infinitum as one studied the cause of the cause, and so on.
For Francisco Sanches, true science is the perfect knowledge of a thing—“SCIENTIA EST REI PERFECTA COGNITIO.” Genuine knowledge is immediate, intuitive apprehension of all the real qualities of an object. Thus, science will deal with particulars, each somehow to be individually understood.
Socrates go beyond this level of scientific certainty, and introduce abstractions, chimeras, and so on. Sanches’s scientific knowledge consists, in its perfect form, of experiential apprehension of each particular in and by itself.
Sanches showed that, strictly speaking, human beings were incapable of attaining certainty. The science of objects known one by one cannot be achieved, partly because of the nature of objects and partly because of the nature of humankind. Things are all related to one another and cannot be known individually. There are an unlimited number of things, all different, so they could never all be known. And still worse, things change so that they are never in such a final or complete state that they can be truly known.
On the human side, Francisco Sanches devoted a great deal of time to presenting difficulties that prevent people from obtaining true knowledge. Our ideas depend on our senses, which only perceive the surface aspects of things, the accidents, and never the substances. From his medical information, Sanches was also able to point out how unreliable our sense experience is, how it changes as our state of health alters.
The many imperfections and limitations, with which God has seen fit to leave us, prevent our senses and our other powers and faculties from ever attaining any true knowledge. The conclusion of all this is that the only truly meaningful scientific knowledge cannot be known. All that humans can achieve is limited, imperfect knowledge of some things that are present in their experience through observation and judgment.
Sanches’s claim that nihil scitur is argued for on philosophical grounds, on a rejection of Aristotelianism and an epistemological analysis of what the object of knowledge and the knower are like. His totally negative conclusion is not the position of Pyrrhonian skepticism, the observation and judgment as to whether anything can be known, but rather the negative dogmatism of the Pyrrhonian skepticism.
A theory of the nature of true knowledge is asserted, and then it is shown that such Sextus Empiricus cannot be attained. The Pyrrhonists, with their more thoroughgoing Pyrrhonian skepticism, could neither assent to the positive theory of knowledge, nor to the definite conclusion that nihil scitur.
|observation and judgment|
Sanches put forward a procedure, not to gain knowledge, but to deal constructively with human experience. This procedure, for which Sanches introduced the term, for the first time, of observation and judgment, “Método universal de las ciencias,” consists in careful observation and judgment and cautious evaluation of observable data.
In advancing this limited or constructive view of science, Sanches was the first Pyrrhonian skepticism to conceive of science in its modern form, as the fruitful activity about the Sextus Empiricus that remained after one had given up the search for absolutely certain knowledge of the nature of things.
Francisco Sanches was influential in his own day and throughout the seventeenth century. Quod nihil scitur was reissued several times up to 1665. Late in the seventeenth century two refutations appeared in Germany. People have seen possible influences not only on Descartes, but also on Pierre Gassendi, Marin Mersenne, Spinoza, and Leibniz, among others, although it is hard to delineate his exact influence as different from that of Montaigne, Sextus Empiricus, Cicero, Charron and other available skeptical sources who were read by most intellectuals of the time.
It may be that Sanches’s formulation of the skeptical problem is closer to the modern idiom than that of any of his contemporaries, including Montaigne, and in terms of how philosophy developed, reads more like a precursor of Bacon or Descartes.