Denis Diderot (1713-1784) describes passions as "penchants, inclinations, desires and aversions carried to a certain degree of intensity, combined with an indistinct sensation of pleasure or pain, occasioned or accompanied by some irregular movement of the blood and animal spirits, are what we call passions. They can be so strong as to inhibit all practice of personal freedom, a state in which the soul is in some sense rendered passive; whence the name passions. This inclination or so-called disposition of the soul, is born of the opinion we hold that a great good or a great evil is contained in an object which in and of itself arouses passion".