OK, Harrison. I’m going to assume critical faculties on your part. You’ve been told that population demographics have been used to calculate the numbers of Jews missing.
Painstaking work has been done going through the records, calculating the numbers of Jews before the War, and then allowing for those who would have died during that time in the natural course of things, allowing for those who would have been killed in the ‘normal’ course of war, and subtracting the number left after the war. We need to take account of those who fled to Britain and America and so on, adjust for those who fled first to one country then another, to make sure we’re not double counting. We need to go through the primary sources and come for pre-war figures for Poland, Hungary, Romania, Netherlands and so on. We can use the Nazi’s own records - they were obsessive bureaucrats. We take cognisance of all the recorded massacres, camps, ghettos. And so on. It is not ever going to be exact, because of the nature of the events, but serious scholars who have painstakingly gone through this process have published their figures, methodologies, working. Others can - and have - then go back to the primary sources and check them. What we end up with is a range of figures from the low 5 millions to the low 6 millions. If a serious scholar says 5.4 million, we aren’t going to quibble. But this is how the figure of around 6 million is arrived at. You can see the published work of people like Reitlinger, Hilberg, Gutman and Rozett, Benz, and so on.