We have apples and Martian oranges here. Whatever exactly biology means by "species" (and there's a debate about that), it's about what the actual science of biology, with its particular set of concepts, theories and empirical claims, uses the term "species" to mean. And so to imagine the word "human" defined only in terms of psychological and mental properties is to imagine a use of the word "human" that has nothing to do with what biologists mean when they talk about species. Once we get to uploading and matrix-style scenarios, we're not even in the same intellectual universe as biology.
This doesn't mean that we shouldn't use the word "human" in a way that's tied purely to the psychological. We can use words however we like. I'd suggest, however, that there's a better word: person as used by philosophers. And so in that vocabulary, your question becomes: if we discovered alien creatures who fit our psychological notion of what a person is, should we count those creatures as persons?
My impression is that most philosophers would say "Yes" without much hesitation—not all, but most. Also: most philosophers would say that if psychological traits are what really matter in deciding what it is to be a person, then there may very well be non-human persons ."Human" in most contexts is at least partly a biological term. But when it comes to how we should treat beings, whether they are biologically human doesn't seem nearly as important as whether they are psychologically like us. Some non-human creatures feel pain. That's a reason not to treat them in certain ways. Some non-human creatures form emotional attachments to other creatures. That's a reason not to separate them gratuitously. And so on.
So I think what you're really asking about is a perfectly good thing to think about, but I don't think it's about species in the sense that that word is used in science. In fact, the word "speciesism" is a term of relatively recent origin that's meant to remind us: what species a creature is shouldn't be where we focus our attention when we try to decide how a being should be treated. What we should concentrate on is what the being is like—especially what it's like psychologically.
We have apples and Martian
We have apples and Martian oranges here. Whatever exactly biology means by "species" (and there's a debate about that), it's about what the actual science of biology, with its particular set of concepts, theories and empirical claims, uses the term "species" to mean. And so to imagine the word "human" defined only in terms of psychological and mental properties is to imagine a use of the word "human" that has nothing to do with what biologists mean when they talk about species. Once we get to uploading and matrix-style scenarios, we're not even in the same intellectual universe as biology.
This doesn't mean that we shouldn't use the word "human" in a way that's tied purely to the psychological. We can use words however we like. I'd suggest, however, that there's a better word: person as used by philosophers. And so in that vocabulary, your question becomes: if we discovered alien creatures who fit our psychological notion of what a person is, should we count those creatures as persons?
My impression is that most philosophers would say "Yes" without much hesitation—not all, but most. Also: most philosophers would say that if psychological traits are what really matter in deciding what it is to be a person, then there may very well be non-human persons ."Human" in most contexts is at least partly a biological term. But when it comes to how we should treat beings, whether they are biologically human doesn't seem nearly as important as whether they are psychologically like us. Some non-human creatures feel pain. That's a reason not to treat them in certain ways. Some non-human creatures form emotional attachments to other creatures. That's a reason not to separate them gratuitously. And so on.
So I think what you're really asking about is a perfectly good thing to think about, but I don't think it's about species in the sense that that word is used in science. In fact, the word "speciesism" is a term of relatively recent origin that's meant to remind us: what species a creature is shouldn't be where we focus our attention when we try to decide how a being should be treated. What we should concentrate on is what the being is like—especially what it's like psychologically.