garbage in / garbage out

Though it is quite possible that for the present that the boasts of political consultancy firm Cambridge Analytica regarding the scope of its role in swaying recent elections is just that—a little immodesty and exaggeration to reinforce their relevance—and perhaps an uncalculated bit of misdirection and subterfuge from the real agents imposing dear costs on rationality and reasonableness, it would nonetheless be ill-advised to be complacent and be unready in the event that such social engineering and manipulation becomes highly effective in the future and that what information we volunteer cannot be used against us.