Hello, SFIA audio listeners, in this month's Nebula exclusive, Big Alien Theory,

we're asking the reason alien civilizations might be rare is because most aliens are huge.

To hear it and every episode early and add free, plus hours of bonus content, check

out Go.nebula.tv slash Isaac Arthur and use my code, Isaac Arthur.

This video is sponsored by CuriosityStream.

Get access to my streaming video service, Nebula, when you sign up for CuriosityStream

using the link in the description.

Science fiction often kicks around terms like the rights of sentient beings.

If that's going to be the standard for how we treat new species that we meet or make in the future,

we better give us some serious thought now to what we truly mean by sentient.

So today we'll be exploring the concept of sentience, what it is and if we can replicate it,

along with the parallel concept of sapiens.

Neither is a very easy concept to define, but that's probably the best

place to begin. Sentience is considered to be the capacity to fear, perceive, or

experience subjectively, and is often considered separate from the faculty of reasoning or

thinking. It is the ability to experience sensations, which tells us both a lot and very little. Sanchez is one of those

fundamental philosophical concepts that is hard not to talk about self-referentially,

but in many ways it isn't just part of what you are, but the bit of you that lets you even

be aware there is a you. We have a classical expression by René de Car, Cajito ergo sum, or I think, therefore I am,

and that's often interpreted as a proof or assertion that the capacity for thought and the capacity

for existence are the same thing, and indeed many folks think it is, but the concept is not

saying that because a rock does not think it does not exist, or even

...