ABSTRACT
Since Hippocrates, the human sense of touch has been the most prevalent and successful medical diagnostic technique. A great variety of diseases were diagnosed through tactile sensing including detection of malignant tumors. Hippocrates in 400 B.C. wrote as follows: “… Such swellings as are soft, free from pain, and yield to the nger, … and are less dangerous than the others. … then, as are painful, hard, and large, indicate danger of speedy death; but such as are soft, free of pain, and yield when pressed with the nger, are more chronic than these…” [28].
