Why can't we perceive extra dimensions?

[Happiness]

String theorists postulate that our world has 9 dimensions and these extra dimensions are very twisted up such that they are too small to be seen.

Question 1:
Why don't we postulate, instead, that the reason we can't see these extra dimensions is because we are not genetically wired to do so, just like a fish or a worm is not genetically wired to understand economics?

Question 2:
What does it mean for these dimensions to be twisted up? Twisted up in where? What I imagine is these dimensions are twisted like a tiny ball of threads; they would be twisted in our macro 3-dimensional space. If so, this picture seems wrong because then they are still existing in our 3-dimensional space, not really being extra-dimensional.

 

[Simon Bridge]

Q1: that's just the same statement but more general and without any testable predictions - i.e. it is "begging the question".
What is it about our genetic wiring that prevents us from seeing the extra dimensions?

Q2: "twisted up" = "lots of curvature". It's maths.
They are not curved in space (in a sense they are space), but have intrinsic curvature like regular spacetime does only more of it.

 

[Happiness]

Q1: that's just the same statement but more general and without any testable predictions - i.e. it is "begging the question".
What is it about our genetic wiring that prevents us from seeing the extra dimensions?

Or maybe some people have the genes that allow them to see the extra dimensions. But when they say they do, we don't believe them.

 

[Drakkith]

Or maybe some people have the genes that allow them to see the extra dimensions.

That is, quite literally, not physically possible. At all. Thread locked since we don't allow speculation of this nature.