Everyone has comprehension of all subject matter on some level. While it is true that the level may be near "nil" in some cases (e.g. nuclear medicine in my case), the level of understanding can be increased once it is related to more familiar ideas. E.g., I took a statistics course a year or so ago and the professor asked (at the onset of his presentation) if we knew what a "cohort study" was. I was not able to explain the statistical process, however, I did know the word "cohort" literally referred to a group of common associates. I suggested to the professor that knowing what a "cohort" is, this statistical method might be somehow related to persons or things with a shared characteristic. He went on to explain the statistics involved. My statistical understanding was enhanced by the prior literal knowledge. I call this "parallel concept application" (PCA). My pebble of knowledge was strictly from the literal. It translated well at the fundamental level of the process allowing learning to proceed. Earlier this week I received a call from a church group who was providing tutorial services to its community. The idea of "perimeter" was a little troubling. I first spoke with the adults about the word "perimeter", which they agreed was simply the measure around the outer edge "something". The idea became clear and the adult was able to work and explain to the child the math idea. Her skill as a retired teacher and avid reader helped her to convey the concept to the child. Most find the process extremely disarming of the stress brought on by unfamiliar math confusion. The process works in grammar as well. (Later)