Humans are machines. But we (and other living things) appear to exhibit defined properties that are not present in complex digital machines. It also seems that what we refer to as self-awareness is an emergent property that living things have, although in theory, not specifically limited to living things.
That set of properties is what is formally defined as having a mind. Whatever that means, and I agree its far from clear what that is.
But -- and its a big but -- digital processes don't seem to be able to mimic or model it (that could be our shortcoming -- the models are not any good) and it isn't just a matter of more memory/processing power/a big enough look-up table. These are not the problem nor the answer. It isn't just a CompSci issue. If it were just that, we would have it licked by now and we would all have interchangeable minds that we could simply reprogram and upload with new sets of skills and belief systems (yes, Robots would definitely need them too, by the way).
We have a long way to go and for a while now we've been heading down the wrong road. But don't take my word for it.