[AdmiralRalwood]

Duh, it's a mathematical ideal, not a physical classification. You might as well call the idea of a square meaningless because you can never have a shape with perfectly straight sides.

"Turing-completeness" is only a mathematical ideal in computational theory; in the real world, it's applied to actual, real-world computers and programming languages.

In colloquial usage, the terms "Turing complete" or "Turing equivalent" are used to mean that any real-world general-purpose computer or computer language can approximately simulate any other real-world general-purpose computer or computer language. The reason this is only approximate is that within the bounds of finite memory, they are only linear bounded automaton complete. Also, any physical computing device has a finite lifespan. In contrast, a universal computer is defined as a device with a Turing complete instruction set, infinite memory, and an infinite lifespan.

A human can simulate any real-world general-purpose computer given enough time and data storage (e.g. paper). Programmers often used to work out the results of their programs on paper before running them on computer hardware.

[Nuke]

i kike how the human brain can do real time inverse kinematics, has robust visual processing capabilities, can run a very large number of control loops and integrate in real time without us knowing its doing these things. yet when we do basic logic and math we are really slow at it. 

the difference between a neural net and a cpu is a matter of chaos. in a cpu you go through great lengths to annihilate chaos in the system. but with a neural net chaos reigns supreme. they are distinctly different systems. just because you can do the job of one on the other (albeit in a really inefficient way), doesn't make the brain a computer.

[Bobboau]

very much depends on how you define computer.

I think it could be called one if we go with:
an object capable of storing and processing data according to instructions given to it in a variable program.

we can do other stuff too, but a subset of our abilities is that definition.

[Nuke]

il admit its rather unfair to compare biology with technology. but there are actually neural net on a chip products that are coming out. so comparing a cpu to a neural net on a chip might be more fair (at least until someone genetically engineers a cpu). still the difference is still pretty big, in structure, performance and ideal application.

[Bobboau]

oh, yeah, not saying it's a good one

[Mongoose]

All I know is that Minecraft claims that it's Turing-complete, so I'll just go with that.