I am building a society where people believe that the past (or today's present) was much worse than it actually was. Freedom = slavery, truth = lies, science = correlation, and so on.
One of the ways they do this is inaccurately comparing lifespan and life expectancy by ignoring mass mortality events. For example, people born before WW2 had a good life expectancy, but a bad life span, because everyone died in a single group of few years which makes the life expectancy loss concentrated in a mass mortality event. I.e., if people live for 20 years with low mortality, then 99.99% of people die, then some small part of that cohort survives and then lives to 80, the average life expectancy is nearly 80 even if almost everyone dies at 20.
Basically the Orwellians argue that the life expectancy in the old times was 30 (based on a few wars in the 20th century) and the life expectancy now is 70 (although in reality there are still wars and disasters, you are just taking a single year life expectancy and not cohort life span). Would this work?
Another tactic is using correlational evidence. Say a medicine is proven to work because you try it in 10000 experiments that each have a 5% confidence interval. 5%*5%*5% means three experiments will succeed in row after 10000 tries. Would this deceive people into thinking their medicine is effective even if they are just spamming studies and selectively data mining?
Another science thing is to make the falls in mortality unrealistic. If I give a medicine to 60% of people and the disease prevalence falls 99% will people be suspicious?
Another tactic is to use atrocities where the picture clearly shows your own side in uniform committing them, but don't mention the uniform. Would people take that at face value, i.e. not check the uniforms?
How do I get my denizens to accept Big Brother in this particular way?