In physics, we can see what can possibly happen to a few particles using energy principle, but to find out what really happens in the next instant would require a knowledge on the forces acting on the particles. For systems involving many particles, energy can also tell us what can possibly happen, but only entropy can tell us what would actually happen. Even so, entropy would not be able to tell us what exactly happens at the microscopic level.

Darwin's theory of evolution tell us what can possibly happen according to the assumptions (scarce resources, excess offspring, random mutation, survival of the fittest, propagation of inherited traits). It can tell us the general trends, but it cannot give us more details than that. It cannot tell whether a tiger would fight back when its children are threatened. However, if such an action aids in its survival and propagation, then the evolutionist can say that a tiger can possibly do that. Still, it would not be able to predict what happens.

However, even forces seem to be unable to explain why things happen; the idea of a force is, after all, a tool used to account for observations, predict future behaviour, and to manipulate the surroundings to obtain the effects we want. So is energy. These things do not necessarily exist. People have lived for a long time without Newtonian mechanics or proper definitions of work and energy, and yet they are still able to come up with many wonderful inventions. Science can only describe nature.

Example:

Why do things fall? Because Fg=-GMm/r² ?

Nope, that is just a description. I don't think there is a "why" to it.

At the end of the day, we'll just have to take it as a fact that Fnet=dp/dt, and that since this "fact" is taken from experience, there will always be a possibility that it is not a correct description.

Which is so gay. Ultimately, all that we have to "explain" phenomena are simply nothing but descriptions? There is nothing that tells me what is actually causing things to happen. Even when taking time as simply another dimension, science still cannot answer "why?"

I suppose we are too used to having "why"s answered for us. The idea of an event being causally linked to another event preceding it is a powerful idea, because it allows us to predict and manipulate the latter event, and allows us to prepare for it. However, just because it works, it doesn't mean it is true.

Gah. Science being a descriptive framework, it would work, but ultimately it cannot answer many questions that we have. I suppose our questions are somewhat loaded. It seems kinda disturbing that things just happen. Maybe it just so happens that humans would want to ask such questions that can never be answered, and we can never be satisfied.

Yet in math, can we ask "why?"

Why is x²+1 always positive for real x? Because x² is at least zero for real x, so x²+1 is always positive for real x. It sounds like we can answer this question. However, what is the point of knowing whether x²+1 is positive? If you assign values to x and use math to find the area, it would work. But even without knowing algebra, one can too show that this similar real life phenomenon leads to such a conclusion. Trial and error would always work if you try long enough.

So is math simply descriptive? What would happen to math if it doesn't correspond to real life phenomena? I suppse math would have to be tweaked in such a way that it does somewhat correspond real life phenomena before it can be accepted. Math is perhaps descriptive to some extent as well.

Darn. So we have been living in this nature, and all we have been doing is describe it? This is... gay.