Joseph Grasset (18 March 1849 – 7 July 1918), was a French neurologist and parapsychological investigator, born in Montpellier.[1]
He received his medical degree (1873) in Montpellier, where in 1881 he became a professor of therapy. In 1886, he attained the chair of clinical medicine, and in 1909 was appointed chair of general pathology.[1]
Grasset was involved in every aspect of internal medicine, but his primary interest concerned diseases of the nervous system. His name is associated with the "Grasset law", 'a condition where a patient with hemiparesis lying on his back can raise either leg separately, but is unable to raise both legs together.'[2]:649 This phenomenon is explained in his 1899 treatise, Diagnostic des maladies de la moëlle.[1]
He conducted studies in the field of psychiatry, publishing the book Demi-fous et Demi-responsables (Semi-Insane and the Semi-Responsible) in 1907, and also researched the paranormal, publishing works with titles such as Le spiritisme devant la science (1904) and L’occultisme hier et aujourd'hui (1907).[1]
His book L’occultisme hier et aujourd'hui was translated into English as The Marvels Beyond Science in 1910. Grasset took a psychological approach to psychical research and attributed mediumship to deliberate trickery or unconscious suggestion.[3][4]