Let's have a philosophical discussion...

Let's have a philosophical discussion. The first question I have for you is do you agree with the proverb that you know a tree by its fruit? Bear with me here.

No.

Why not?

Hi bear

All proverbs invariably have their insights, their uses and their limits.

Because different processes can have the same results.

Actions speak louder than words, yes?

Certainly it would seem so Socrates!

the intentions remain hidden

That's generally true in most cases, unless inquiries are made. Inquiries themselves don't magically pre-empt lying, however. But in the case of theft (for instance) video cameras do, in which case the now known 'thief' can accept 'being known by his fruits' or not, in which case he'd be a pathetic liar as well (an even sicker tree).
But the dictum is meant in a more general sense, I think. Somehow over time (we) almost inexpressibly come to know the persons we live around- who to trust, who not to trust, who to ask a favor, who not, etc.

Someone give me a sound argument as to why it's okay to eat meat.

it's a good source of energy

There are other good sources of energy that don't require killing sentient creatures.

it's my turn to ask so pls give me a sound argument why it's bad to kill animals for food

to fulfill our basic primal urges and dominate other less sentient beings. it also fulfills out role in the food chain as the top predator. ironically, our meat eating ensures the long term survival of a couple of species.

Whats the point about having discussion over metaphysics when the whole point of metaphysics is that nothing will ever be observable enough to prove any of it?

If the question is "Can you judge something by what it produces," then I disagree.

If the question is "Can you judge something by its origin," then I disagree also.

If the question is "Can you make a guess at where something came from based on how it looks," then sure, yeah.

i was referring to the intentions-as in the motivations behind an action. to take your example, the thief could have been a dangerous criminal or a poor man trying to provide for the family. you cannot tell which of those he is. people do good things for bad reasons and bad things for good reasons and end up misjudged because of their fruits
you can say he's a thief and that's all, in this regard actions do speak louder than words but they dont say much about the tree in itself except that it has grown those certain fruits
>But the dictum is meant in a more general sense
totally so
at least one of us still has faith in the people he lives with

Preference maximization, dude.
Animals are conscious and capable of feeling pain.
To inflict pain and end a consciousness without necessity is wrong.
Therefore, killing animals without necessity is wrong.

>it's in our nature
As rational creatures, we have an obligation to stray from the way of nature when rational analysis deems that certain aspects of nature don't "fly" in a modern society. For instance, many simians rape, yet we recognize this is wrong despite it being rooted in our human nature.
A tiger is never given a chance to think if it ought to kill a goat. Humans have that chance, and we should take it.

Yes both figuratively and literally. You can learn a lot from just a sliver of information.

Different processes can produce the same thing, and if you're in a non-linear domain, there's no connection between the process and the outcome.

Animals don't care about you, you shouldn't care about them.

I think it's entirely possible to desire another creature's well being even if they don't give a shit about mine, or even if they actively want me not to succeed. Our entire justice system is built on that concept.