We just had a terrible thought. What if none of this is real?

What if we are just a brain in a vat, and a scientist is probing us with electrodes? The feeling of these fingers typing on the keyboard as we write this profile? It's not real! These fingers are not real! This profile is not real! This website is not real! We are not real! Nothing is real! We are just a brain in a vat!

Putting aside the fact that this profile, is, well, not "real" (it's just 1s and 0s on some server in Oregon) and that this thought is not exactly original (it's an extension of Rene Descartes' evil demon idea, and many philosophers have battled with it since) — don't worry about it!

According to philosopher and mathematician Hilary Putnam (yes, it's a Jewish man named Hilary), it makes no sense. His reasoning says that a brain-in-a-vat will have no reference point to what a brain is or a vat is. To understand the scenario of someone putting a brain in a vat, you need to have the vantage point of someone who can actually put a brain in a vat, so the scientist (G-d) in this scenario. And you are not G-d, so you can also not be a brain-in-a-vat! Does any of that make any sense?

Some philosophers don't buy Putnam's reasoning. To them, it seems possible that we are all just brains in vats.

Maybe the scientists who are probing us are brains in vats too?