Left: René Descartes Right: Meditations (1641)

Picture this: you open your laptop; you’re met with your familiar login screen; you enter your password; the login screen goes away; you’re now logged in; you see all your familiar icons; everything seems normal.

But you have a nagging doubt. What if what you see of your desktop is not actually your desktop but a program installed on your machine by a malicious hacker. This program makes it appear as if everything you see is your computer but it’s actually a skin over the original. You click on an icon and the original program opens up but what’s actually happening is that your mouse is just sending a message to the hacker’s program which then opens — as proxy — the original program (or, a facsimile of the original).

If you’ve ever had this doubt, that’s great. Paranoia is a sign of Good Health.

More importantly, René Descartes, Enlightenment polymath — mathematician, physicist, and philosopher — had the same thoughts. He would’ve fit right in with our modern day Computer Security folks. Centuries before Bill Gates made the PC a household name (1980), before Charles Flint founded IBM (1911), and even before Charles Babbage’s Analytical Engine (1837), Descartes had this to say in his Meditations on First Philosophy, (1641):

I will suppose… that there is… a malignant genius, as powerful as he is cunning and deceitful, who has used all his zeal to deceive me;… and… every external thing we perceive, are… illusions… which this Demon has laid traps for my credulity.