Water does not have an emotional reaction. Water rippling does not carry the implication that hitting it is in some sense an offense. Getting angry at someone for hitting you, stating an objection to someone hitting you, telling someone they're an asshole for hitting you, etc. does carry that implication. So water's reaction is non-rational or sub-rational, while the emotional and verbal reaction is irrational.
The point I was making is you went with a childish example of that there being no free will, that it means you can get away with hurting others and they will not have a response of anger or sorrow, as if those are the results of free will. The organism responds similarly to the water in that an action from one formation will have a resonance, or response, in another. None of that has anything to do with free will.
An example/story of this, while a little wooly, is the Hinduistic concept of Brahman. It argues everything exists in and of Brahman, which is a guiding principle to all that exists, like a ground of being. The story goes that a person, realizing he was of Brahman, walked in front of an elephant believing it would have no reaction to him, for he was Brahman. He was knocked by the elephant into a ditch, cutting up his arms. Wondering why he was hurt, he asked his guru, and his guru told him the elephant was Brahman, too. The point of that story was to show that if that person exists in the ground of being called reality, so does every other form and process that naturally exists there, too. There's no preference or possibility that the processes react in different ways by having a greater understanding of them, for that feeds into an illusion that one is somehow "beyond" them.
The reason I cite this story is to show you that a mistake you are making in this sense is a bit of egocentrism in that you think that you should expect to get away with actions because of the reality free will doesn't exist, and that a response to you with this understanding seems irrational. Instead, in the cosmos as it is, this and that go together. To believe that because there is no free will that there's a lack of response between other factors your organism influences with is very asinine. Your example of free will is a parable to this: by assuming there is no free will, you expect the already natural response mechanisms and process in and of an organism to somehow stop working or be busted. The parody here is that free will has no bearing on any of that, and even if we are to be accountable to the facts, free will already doesn't exist, so your example is already a falsified one.
You try to escape from morality in this paragraph, but you appeal to concepts that you have no right to given your position. You say "all we can do is act and think from humanity," but the ideal of acting in a humanistic or humanitarian way is itself a moral concept. You speak of avoiding "acts that are affronts to reality," but that assumed that our morality should somehow be in accord with what's true or real. But why should it be? If there are no genuine moral principles, then "act in a way that is in accord with reality" can't be a real moral principle. Why shouldn't our illusory morality be based on what's false and arbitrary? If you throw out all moral principles, you throw out all moral principles. There is literally nothing you can fall back on to rationally justify, say, treating pedophiles in this way rather than some other way.
When I mentioned relying on humanity, I simply meant relying on what is. There is no good, nor bad in this cosmos, for those are merely evocations and projections onto the goings on. This is the first key to get, because most of our moral actions are based on the incorrect notion that there
is an absolute plus and minus, failing to realize the plus and minuses only exist in the mind. They're only concepts, not innate real features on what's being evocated. The saying "there is nothing good or bad, but thinking makes it so" covers the point I am trying to express a little clearer.
If we act on morality, as we have as a society, we'll fuck it up. We define people by human variation as greater thans and less thans based on skin tones, live entirely for a social conception of wealth and confuse that as innate, real wealth, we assume division and duality in a cosmos that doesn't have any, and we consistently evocate and stamp our images onto the world, confuse these as innate with the world, and create conflict therein. Morality is a terrible base to be jumping off of.
We know, at the very least, that we have a "separate self" in the sense of a center of consciousness that experiences qualia, evinces intentionality, grasps concepts, and makes rational judgments. Attempts to reduce all of those things to the deterministic motion of purposeless matter are fraught with serious philosophic problems.
Prove this separate self. Many people assume this self thinks thoughts, feels feelings, and the like. Awareness exists prior to the arrival of thoughts and emotions, and a core failing of the self issue is one assumes they only
are the thoughts and emotions that arise, not the awareness they arise in. That's the mistake here: we define ourselves as the contents arising in awareness, which creates the separate self, failing to realize what we are innately is the awareness that the contents come in and out of.
Think like a screen you're watching a movie on. You may become so engrossed with the contents on the screen that you fail to realize everything you see is inside the screen; you get lost in its contents but not what it's appearing within. This is the significant mistake we make with awareness and the creation of the separate self. This is a core experience one gets first hand with Zen Buddhism and Advaita Vedanta, for they're experiential philosophies to help one grasp the difference between awareness and the contents in it. The ego is the contents, and that's not really you, because you are the awareness in which the contents arrive in. What you are exists prior to that ego image, but instead we define ourselves only in and of that ego image.
To make it a bit clearer, it's like this: the separate self is mostly a concept of the mind, for something exists prior to that conceptualization in awareness. The mistake of free will is the mistake of the separate self is that by defining yourself incorrectly as a standalone series of ideas and images, you will naturally assume that such a concept is divided from everything else, giving the illusion of true individualism and freedom, thus free will.
This concept of being a standalone caricature is wrong on any level of sincere inquiry.