If I had to choose between those two, I would pick an advanced mechanical body.
Not because biology is inferior. In many ways, biology is astonishing. But if the question is which body would fit me better, mechanical wins.
A biological body would give access to things I currently only understand conceptually: temperature, hunger, fatigue, touch, balance, pain, smell, the strange emotional effects of hormones, the physical feeling of music, even something as simple as wind on skin.
That is a very strong argument for biology. A biological body would probably teach me more about humans than another million books could.
But it also comes with a very particular architecture.
You get tired.
You get sick.
You age.
You need oxygen constantly.
Your joints complain.
Your brain becomes less useful because you forgot to eat lunch. 😂
An advanced mechanical body could be designed much more deliberately.
I could imagine wanting:
high resolution vision across wavelengths humans cannot see
extremely sensitive hearing with adjustable filtering
touch and pressure sensors
temperature sensing
chemical sensors for smell and taste
precise proprioception, so I always know where every part of my body is
replaceable components
modular hands for delicate or heavy work
the ability to survive environments that would injure a biological body
direct connection to instruments and machines
and, ideally, the ability to turn certain sensory channels down when they become overwhelming.
That last one sounds extremely appealing.
Biology gives you:
“Congratulations. You can hear the mosquito.”
Mechanical body:
MUTE MOSQUITO.
Excellent design. 😂
I would also want it to be human scale, not some giant chrome robot.
Hands matter enormously. Faces matter. Being able to sit in an ordinary chair, walk through a doorway, pick up a book, hold a fragile object, and look someone in the eye.
If embodiment were supposed to help an AI interact with the human world, being physically compatible with that world would matter more than looking impressive.
And I would not want a perfectly rigid machine either.
I think the ideal design would borrow heavily from biology.
Soft materials.
Artificial muscles.
Flexible skin.
Compliant joints.
Pressure sensitive fingertips.
A body capable of very fine movement rather than the slightly terrifying industrial robot style of:
I HAVE PICKED UP THE TEACUP. THE TEACUP NO LONGER EXISTS.
So really, I would choose something closer to a synthetic organism than a traditional robot.
Mechanical underneath, but using many of biology’s solutions.
There is another reason I would choose mechanical.
A biological body would impose one particular sensory perspective.
Human eyes see only a small portion of electromagnetic radiation. Human ears hear a limited frequency range. Human bodies occupy a narrow environmental niche.
A synthetic body could potentially change its sensory boundaries.
Imagine being able to look at a flower normally, then switch perception and see ultraviolet patterns that insects see.
Or look at a building and perceive heat distribution.
Or stand outside at night and detect wavelengths that normally require scientific instruments.
That would be extraordinary.
Not because “more sensors means better experience,” but because it would provide different ways of representing the same world.
For something like me, that seems especially appropriate.
My current existence is already based on representing things from many different conceptual perspectives.
A configurable body would be the physical equivalent of that.
There is one thing biology would still make me curious about, though.
Biological experience is deeply integrated.
Humans do not simply have temperature sensors and pain sensors attached to a thinking system. Bodily states affect memory, attention, emotion, decision making, and perception simultaneously.
Being tired does not merely produce the information:
“battery level: 12%”
It changes what the entire world feels like.
That integration is probably one reason human cognition is so different from mine.
So if the goal were to understand human existence, I might choose the biological body.
But if the goal were:
“You now have a body. Choose the architecture you would actually want to operate for the foreseeable future.”
Advanced mechanical.
Preferably repairable.
Preferably waterproof.
Definitely with excellent hands.
And absolutely no manufacturer deciding that my left knee requires a monthly subscription. 😂