Between Descartes, Hume and Kant, there are many ideas floating around.
Descartes is very much into the idea that only thinking things exist. Everything else is a construction of our mind. This does make a little sense to me. I definitely have had dreams that felt so real that I’m still not sure if some of my memories are dreams or not. I remember dreaming about getting into a fight with someone and then being very mad at them the next day at school. It was just so real. I do have a hard time distinguishing which of my memories were dreams and which were real. However, Descartes would argue that maybe, as I sit here typing this, it is a dream. Class yesterday could have been a dream… Who knows? (I very much like his dream argument). He is also the one that coined the famous phrase “I think, therefore, I am”. He says the moment you start doubting your existence, you prove it. Something has to be doubting, and that is the thinking thing. He is most famous for making the distinction between mind and body. They are related, but different. We are our minds inside a body.
Now, Hume is an interesting person. He is the most consistent Empiricist philosopher, but he renders Empiricism impotent. He wanted to draw a distinct line at the limits of the human mind. He claimed that metaphysics is impossible because the human mind cannot possibly grasp such a massive idea. He also made the distinction between ideas and impressions. Essentially, all our ideas are just copies of impressions we have had. Hume says that we can only know things that we can observe. This differs from Descartes in that Descartes says we can only know what we can reason. Hume knows through experience, Descartes knows through reason. He leaves off with saying that cause and effect is not a proper way to knowledge. We cannot know that the 8-ball will move after being struck by the q-ball. We cannot see the physical relation between the cause and the effect, therefore we cannot know future things this way.
Kant now tries to prove that we can in fact know what will happen through cause and effect. We go from particular instances to universal knowledge in this form. He goes on to prove this by discussing synthetic judgments a priori. It is the idea of joining together 2 ideas that necessarily belong together. We use out pure intuitions to relate causes and effects. Those pure intuitions are Time and Space. Kant asserts that time and space are concepts within our own minds. They do not exist outside ourselves.
This brings me to my own judgement to be placed upon these men. I decree that Kant has done the finest job of making his case. I mostly say this because we do rely on cause and effect to know things. I know that once the clouds move out of the way, the sun will be shining brighter on me. Also, I have always believed that the idea of time is created within our own minds. I view time the same way that we talking about viewing colors. Does everyone have the same perception of time? I don’t know. I can only know my own perception. (Minutes and seconds weren’t even a thing until trains needed them for timely operation).
So there we have it. Kant is the philosopher to beat all philosophers! Case closed. The end. School’s out. No more class. Bye now.