What Does It All Mean? A Very Short Introduction to Philosophy2

The most radical conclusion to draw from this would be that your mind is the only thing that exists. This view is called solipsism.

The main concern of philosophy is to question and understand very common ideas that all of us use every day without thinking about them. A historian may ask what happened at some time in the past, but a philosopher will ask, "What is time?" A mathematician may investigate the relations among numbers, but a philosopher will ask, "What is a number?"

In fact most of the time you don't even think about the mental states that make you aware of those things: you seem to be aware of them directly. But how do you know they really exist?

Knowledge of minds other than our own
The relation between mind and brain
How language is possible
Whether we have free will
The basis of morality
What inequalities are unjust
The nature of death
The meaning of life

There may or may not be an external world, and if there is it may or may not be completely different from how it seems to you -- there's no way for you to tell. This view is called skepticism about the external world.

Would things seem any different to you if in fact all these things existed only in your mind -- if everything you took to be the real world outside was just a giant dream or hallucination, from which you will never wake up?

Is your mind something different from your brain, though connected to it, or is it your brain?

what can you really know about the conscious life in this world beyond the fact that you yourself have a conscious mind?