Historical Alchemy doesn't exactly include the law of equivalent exchange in the manner that it appears in the Japanese series Fullmetal Alchemist. While it is true that you can't create something out of nothing, there is a lot more to Alchemy than the idea of transmutation (however, this is a running theme, be it metals, the soul, etc. All Alchemic practices at the core are about the process of betterment and change, no matter what you are looking at).
While MindlessChaos has a point that every culture teaches about consequences, I wouldn't necessarily call it a cosmic fact. In science, we do observe every action creating affect and altering everything around it, even if only slightly, but there are a lot of things that don't necessarily fall in the parameters of 'good' and 'bad'. For example, a predator hunts prey, and while it can be looked at as good on the side of the predator and bad on the side of the prey, it is both and neither on the whole because it is a natural order of life and death. The predator doesn't inherently receive negative repercussions for taking down prey. The point being that not everything will fall in line with someone's beliefs.
As for the bit about black and white magick; they are accepted by many as simply labels for intent and nothing more. To say there is no such thing is also a matter of whether or not it is a part of your path and if you choose to use labels for intent, go right ahead. If you choose not to, go right ahead. There are uses for colors within magick, but as I just pointed in my last paragraph, they will not fall within universal parameters.
In closing, everything you do will affect everything around you. You can choose to believe that you'll receive good or bad consequences, but that is up to you. The only fact set in stone is that every action will have a consequence. This is a scientific truth.