## Falling & pain

It’s not the fall that kills you; it’s the sudden stop at the end Douglas Adams Obviously, just carrying momentum is no problem; a free…

## Cause & effect

Friction, $f_s$ or $f_k$, and the normal force $n$ are obviously reaction forces, since they are never there unless something else pushes. Other forces are…

## Time

What exactly is time? You might say: ‘time is duration’ or ‘time is how long something lasts’. But that’s circular; that’s like saying ‘time is…

## To exist

When born, we know nothing. Not how the world works; not even that a world exists. Then we open our eyes for the first time.…