Self-study
Conclusion If there are sentient beings on planets outside our solar system, we will not be able to determine this anytime in the near future unless some of these beings are at least as intelligent as humans. ██ ████ ███ ██ ████ ██ ████ ██████████ ██ ███████ ███████ ███ █████ ██████ ███████ ██ ███ ████ ███████ ███ ███ ████████ █████ ██ ███████ ██████ ███████ ██ █████████████ ████ ██ ███████ ██ ███ ████ ██████ █████ ████ ██ ██ ██ █████ ██ ███████████ ██ ██ ████
Summary
The author concludes that if there are sentient beings on planets outside our solar system, then if we can determine in the near future that those beings exist, some of those beings must be at least as intelligent as humans.
Why?
The author tries to reason by process of elimination.
First, we can’t send spacecraft to planets outside our solar system in the near future. (The author thinks this implies that one way for determining the existence of sentient beings is ruled out.)
In addition, in order for the sentient beings to be able to communicate with us, they need to be at least as intelligent as humans. (The author thinks that because we’ve ruled out sending spacecraft to other solar systems, we have to go down this path in order to determine that sentient beings in other solar systems exist.)
Missing Connection
The author assumes that in order to determine whether sentient beings on other solar systems exist, we must either send a spacecraft to those systems or those beings must be capable of communicating with humans. This is why the author thinks that, because we’ve ruled out the spacecraft option, we need the sentient beings to be able to communicate with us; this in turn requires that they be as intelligent as we are.
18.
The argument's conclusion can be ████████ ████████ ██ █████ ███ ██ ███ █████████ ██ ████████
a
There are no ████████ ██████ ██ ███████ ██ ███ █████ ██████ █████ ████ █████ ██ ██████
The argument concerns the existence of sentient beings on planets OUTSIDE our solar system. Whether there are sentient beings other than humans in OUR solar system is irrelevant.
b
Any beings that ███ ██ █████ ██ ███████████ ██ ██████ █████ ████ ██ ███████████ ████ ████████ ██████ ███████ █████ ███ █████ ████████
We’re trying to prove that determining the existence of sentient being in other solar systems requires that they be at least as intelligent as us. (B) establishes that IF there are beings at least as intelligent as us, they would want to communicate with other sentient beings. But this doesn’t prove anything about whether they NEED to be at least as intelligent as us in order for us to determine they exist.
c
If there is █ ████████ █████ ██ ███████ ██████ ████ ██ ██ ███████████ ██ ██████ ████ ██ ████ ███ ██ ████ ██ ████ ██████████ ██ ███ ███████ ██████ ███████ ██ ███ ████ ███████
We already know from a premise that we can’t send a spacecraft to planets outside our solar system. So it doesn’t help the argument to establish some condition that would prove we can’t send a spacecraft to a planet; we already know this. Also, we’re trying to prove that a sentient being in another solar system NEEDS to be as intelligent as us to determine that they exist; (C) establishes what happens IF there’s a sentient being as intelligent as us. That doesn’t prove that they NEED to be as intelligent as us.
d
If a sentient █████ ██ ███████ ██████ ██████ ███████████ ████ ███ ████ ███ ████ ███ ██ ██████ ███ █████████ ██ ██ ███████ █ ██████████ ██ ███ ███████
(D) establishes that the only two options for determining the existence of a sentient being are sending a spacecraft, or communicating with it. We know we can’t send a spacecraft, so that establishes we have to be able to communicate with it. And we know from a premise that communication requires that the sentient being be as intelligent as us. That’s why in order to determine the existence of those beings, they must be as intelligent as us.
e
Any sentient beings ██ ███████ ███████ ███ █████ ██████ ████ ███ ██ █████ ██ ███████████ ██ ██████ █████ ██ ███████ ██ █████████████ ████ ███
We’re trying to prove that a sentient being in another solar system NEEDS to be as intelligent as us to determine that they exist; (E) establishes what happens IF there’s a sentient being as intelligent as us. That doesn’t prove that they NEED to be as intelligent as us.