28. Realism?

The question still stands: do we know the world as it is? According to the empiricists we know it through elementary ‘sense data’. According to idealists it is all in the mind. I argued that we see and conceptualise the world according to mental categories that we develop in interaction with the world. That effect of the world on our thought yields a form of realism. However, this implies the assumption that the world exists. On what is that based?  

We cannot prove that reality exists but we can hardly do other than make the assumption, as a ‘natural belief’, as the 18th century philosopher Hume already said. The philosopher Heidegger also argued that we cannot do other than think in terms of being, of a world that exists. It would be difficult to make sense of our life and the world without it. If the world does not exist, how could we have developed ideas to survive in it? But this argument is circular, assuming a world to survive in.

To believe in evolution we need to believe in a reality that forms a selection environment. Let us assume that this reality indeed consists of objects in space and time, things, animals and people that act. Especially those are salient for functioning and survival in the world. We would not have survived if we hadn’t formed a reasonably adequate mental representation and understanding of them. And that implies that we have an inclination to categorize in such terms of time and place, form, volume, matter, mass, place and movement. Those were of predominant importance to find food, hunt prey, and escape from the sabre-toothed tiger. As Gilbert Ryle indicated in 1949, ‘intelligence’ does not refer to some psychic object, but to a constellation of capabilities, inclinations and practices. All this does not prove that reality is indeed as postulated, but it does form a coherent argument. That view of reality, plus evolutionary theory, and an explanation of our survival and the consequences for our thought then form a coherent whole. That makes the assumption of external reality a warranted belief, even though we cannot prove it. Admittedly, it is like a house of cards: different elements supporting each other. Not strong perhaps, but still better than a single card.