quality:correction
Cartesian

One of the last notable philosophers to accept something like the Aristotelian "common sense" was Descartes in the 17th century, but he also undermined it. He described this inner faculty when writing in Latin in his Meditations on first philosophy. The common sense is the link between the body and its senses, and the true human mind, which according to Descartes must be purely immaterial. Unlike Aristotle, who had placed it in the heart, by the time of Descartes this faculty was thought to be in the brain, and he located it in the pineal gland. Descartes' judgement of this common sense was that it was enough to persuade the human consciousness of the existence of physical things, but often in a very indistinct way. To get a more distinct understanding of things, it is more important to be methodical and mathematical. This line of thought was taken further, if not by Descartes himself then by those he influenced, until the concept of a faculty or organ of common sense was itself rejected.

René Descartes is generally credited with making obsolete the notion that there was an actual faculty within the human brain that functioned as a sensus communis. The French philosopher did not fully reject the idea of the inner senses, which he appropriated from the Scholastics. But he distanced himself from the Aristotelian conception of a common sense faculty, abandoning it entirely by the time of his Passions of the Soul (1649).

Contemporaries such as Gassendi and Hobbes went beyond Descartes in some ways in their rejection of Aristotelianism, rejecting explanations involving anything other than matter and motion, including the distinction between the animal-like judgement of sense perception, a special separate common sense, and the human mind or noûs, which Descartes had retained from Aristotelianism. In contrast to Descartes who "found it unacceptable to assume that sensory representations may enter the mental realm from without"...

According to Hobbes man is no different from the other animals. Hobbes' philosophy constituted a more profound rupture with Peripatetic thought. He accepted mental representations but "All sense is fancy", as Hobbes famously put it, with the only exception of extension and motion.

But Descartes used two different terms in his work, not only the Latin term " sensus communis ", but also the French term bon sens, with which he opens his Discourse on Method. And this second concept survived better. This work was written in French, and does not directly discuss the Aristotelian technical theory of perception. Bon sens is the equivalent of modern English "common sense" or "good sense". As the Aristotelian meaning of the Latin term began to be forgotten after Descartes, his discussion of bon sens gave a new way of defining sensus communis in various European languages (including Latin, even though Descartes himself did not translate bon sens as sensus communis, but treated them as two separate things).

Schaeffer (1990, p. 2) writes that "Descartes is the source of the most common meaning of common sense today: practical judgment". Gilson noted that Descartes actually gave bon sens two related meanings, first the basic and widely shared ability to judge true and false, which he also calls raison (lit. ' 'reason' '); and second, wisdom, the perfected version of the first. The Latin term Descartes uses, bona mens (lit. ' 'good mind' '), derives from the Stoic author Seneca who only used it in the second sense. Descartes was being original.

The idea that now became influential, developed in both the Latin and French works of Descartes, though coming from different directions, is that common good sense (and indeed sense perception) is not reliable enough for the new Cartesian method of skeptical reasoning. The Cartesian project to replace common good sense with clearly defined mathematical reasoning was aimed at certainty, and not mere probability. It was promoted further by people such as Hobbes, Spinoza, and others and continues to have important impacts on everyday life. In France, the Netherlands, Belgium, Spain and Italy, it was in its initial florescence associated with the administration of Catholic empires of the competing Bourbon, and Habsburg dynasties, both seeking to centralize their power in a modern way, responding to Machiavellianism and Protestantism as part of the Counter-Reformation.

Cartesian theory offered a justification for innovative social change achieved through the courts and administration, an ability to adapt the law to changing social conditions by making the basis for legislation "rational" rather than "traditional".

So after Descartes, critical attention turned from Aristotle and his theory of perception, and more towards Descartes' own treatment of common good sense, concerning which several 18th-century authors found help in Roman literature.