Can the human brain run software unaided?

Not unaided, no. I mean… you’d need a USB port or a CD-drive to get it in there.

You can’t “install” software into your brain. Running software in your mind would just be using your imagination and/or logic and reasoning.

It’s probably feasible, but I don’t think that it’s something that we’ll be able to do anytime soon. The brain is designed to interface with the world via the senses, not network; as such, we would have to either find a way to install the software visually, aurally, or tactually, or devise another input mechanism.
And it would have to be written specifically for the brain. And it would be more reliable to co-opt the occipital lobe rather than hope for imagination to pick up the slack.

There isn’t a very simple program that could be run? For instance when does a calculation become a program? 2+2=4 That’s like a program!? Right?

The human brain is hardware and its software is the imagination.

Software is a set of instructions. We can certaintly follow instructions.

I think as an additional stipulation for “software” you’d have to at least say it consists recorded instructions that are followed later.

And if you’re reducing software to that you can say a lot of life other than the human brain can run software. Genes could be considered software, grass could be said to “run” a growing program when conditions are right and use that to multiply cells as needed.

So I think if you’re going to reduce your terms down to that basic a level, you could basically say any life form can run software.

Because you ask about the human brain specifically, it seems like you’d want to have a more structured definition for software. Maybe adding something to do with an interpreted language or repeatable, consistent results?

Absolutely, but you have to write it in the language of the mind which would probably resemble something like machine code but much more complex.

Define “software”.

If you mean the 1s and 0s stuff that computers use then no, for much the same reason that you can’t watch movies on a cassette player. The brain is not purely electrical, nor is it binary.

If you mean some other sort of programing, then hypnotism qualifies.

The human brain runs thousands of software programs simultaneously, all the time. Each meme constitutes a background process, which combine to run higher level programs. The most remarkable of these programs is consciousness.