When asking myself basically, what do you know, then I can only come up with the following. Space. Well what is space? Is it anything at all? We can measure distances between material objects, and we call the distance between them as the 'space' between them. Space is not realy something, which does not contradict the fact that it contains things. Abdolute everywhere in space there is something. Space has properties. They are the dimensions of space. There are three dimensions, cause there are three dimensions you can go in space. Any other direction you fo in space can be expressed in terms of these dimensions. How large is space? Well in fact, there is no end to space. Suppose there would, what would then be on the other side? That is not thinkable (space being finite), space must therefore be endless. Existence. Well I know about a lot of things that exist. So many, and with so many properties, I can not name them here. But how do I know they exist? In fact, I do not, at least I do not know if I know that everything exists, but the hypothese is workable, and never left me in the dark. I can try to assume that nothing is existent. But no matter how hard I try, I still come up with the fact that there is me there, thinking this. The hypothese of everything being just an imagination is therefore something ridiculous. If there would be nothing existent, then also there could be no thinking. Who would be imagining the things then? Knowing How do I know if I know something? I do not know that. I can try to find out if I know something. How can I say something? The moment I realy try to know that, and realy dig into it, all that I can find out is that I can not speak. I feel it is just impossible to conduct my muscles and all that is involved in speaking in such a consciouss way, that I know what speaking is all about. Yet I am able of speaking, when I am not wanting to know how I can speak. Do I know how to speak when I am speaking? I know I can speak. Only I do not know how I am speaking when I speak. What more needs one to know?