Not all knowledge is necessarily science. That's the point I am making. As you say, metaphysical knowledge can be gained through observation and the application of logic.
I agree. All knowledge is visceral and visceral knowledge can come from many sources including the mere "muscle memory" that underlies some great skill. Visceral knowledge is as much an "art" as a science.
This process is especially relevant when it comes to Aristotelian metaphysics. Metaphysics can also establish knowledge without the need for observation. For example, Descartes 'cogito'
I strongly disagree. It's always garbage in garbage out. In Descartes' case it's language in language out and the language just happens to be garbage like all modern language.
There are many creatures that venture into my backward by way of flight, stealth (foxes) straying (dogs), or burrowing. Some creatures actually stay and wait for me to feed them. I could try and explain to these animals the elements of the scientific method. I could do this until I am blue in the face, but they would never understand science.
Animals don't understand the nature of experiment so can never understand modern science. They do understand observation naturally and their science is based on this and the logic of nature encoded in their brains largely as language. Humans lost this logic when the ancient language failed so we've codified it in math and allow reality to determine what we learn from science by its effect on experiment. Modern science generates a great deal of technology but little understanding. We believe we understand because of the confused language that underlies our means to interpret experiment and the illegitimate extrapolation of theory (experiment) to nature.
I think therefore I am is mere claptrap. You can't think at all without language and modern language has to be taught to us. Animals, babies, and ancient man didn't need to think themselves into existence. Beavers didn't need to learn modern science to invent dam building.