periodic table- Brute fact (Wikipedia)
In contemporary philosophy, a brute fact is a fact that cannot be explained in terms of a deeper, more “fundamental” fact. There are two main ways to explain something: say what “brought it about”, or describe it at a more “fundamental” level. For example, a cat displayed on a computer screen can be explained, more “fundamentally”, in terms of certain voltages in bits of metal in the screen, which in turn can be explained, more “fundamentally”, in terms of certain subatomic particles moving in a certain manner. If one were to keep explaining the world in this way and reach a point at which no more “deeper” explanations can be given, then one would have found some facts which are brute or inexplicable, in the sense that we cannot give them an ontological explanation. As it might be put, there may exist some things that just are.