spuriousmonkey said:
who cares what a fact is. Evolution is a theory.
but a theory isn't suposed to have its basis on facts, and explain others?
eddymrsci said:
I don't think evolution is a fact, as far as a know, it's only a supported theory, at least for now. I don't think any living human being has actually witnessed the process evolution - because it started so long ago, and it lasted so long (and it's still going right now). The only thing we can do is to find evidence or proof to support that this event happened before.
Can something be
happening right now and not be a fact? If it can't be called a fact, we're suposed to say that it
seems to be happening right now, to account the possibility of being somehow a illusion.
I think that the point maybe is the thing of being both a fact and a theory.
By "theory of evolution", eventualy is meant "natural selection" or "common ancestry". These are theories, but simply "evolution" - descent with modification - is a clearly a fact (and theoretically unavoidable, or better, only in theory it's avoidable, under ideal conditions).
From the fact that living beings reproduce, and their descent is modificated, we can theorize that nowaday's living beings are modified descendants from living beings of the past. The fossil registry shows exactly the pattern that would be expected if it had happened from what we know about heredity. We don't find things like mammal polyps, or "vertebroid" squids - with vertebrae-like tentacles and cranium, hexapod dragons or pegasus, etc. Furthermore, we do not observe any alternative explanation for the existence of the nowadays lifeforms, such as sporadic spontaneous generation of new species.
By that, I would at least informally say that evolution or common ancestry is a fact, at least generaly. A specific phylogeny, although, I'd say that is theoretical. I could call it also a fact, with enough evidence to support, although.
I don't see what is the problem in saying that evolution, meaning common ancestry, natural selection, or simply descent with modification, are facts. If there's, it's in the same level of problem than saying that is a fact that I descend from my parents, so is something abuot formal rules, or something deeply philosophical. If there are some scientific formal rules that forbid calling evolution I fact, I don't know since I'm not a scientist, and I guess that lots of scientists also don't know.