This week, John and Ken ponder the connection between the mind and the world. What is the mind? How do we know there is a physical world out there? If there is, what is it made of and how is it different from the internal mental life that each of us inhabits? John and Ken are both pretty sure that there is a physical world out there, but the special guest, Howard Robinson, seems to think that might not be the case. How on earth can a philosophically minded person navigate these treacherous waters?

Well, we can always start with common sense. The commonsense view seems to be that there is in fact a physical world out there, and that we all live in it. Science is at least intuitively grounded in this view, and it’s given us some very impressive knowledge about the way things work—but what does it really tell us about what is out there? Some people believe in souls, and many more believe in God. Are we to believe that souls or God are physical entities? What about free will? Even if our minds are physical, what about God’s mind? Since Descartes, these lofty questions have preoccupied philosophers, and there are a few well-established views.

First, there’s the view called ‘monistic materialism.’ This refers to the idea that everything out there is physical—minds (and perhaps God) included. Others think that there is a physical world out there, but minds are not a part of it. We call these people ‘dualists.’ Finally, there is ‘idealism,’ and view espoused by the likes of Berkeley and Howard Robinson. Idealists hold that there is only one type of entity, and that is the mental type.

To Howard, the fundamental question is about the nature of matter. Although science has told us quite a bit about what matter does and how entities relate to one another, there is no clear conception of what it is. Yet, most of the qualities we attribute to matter are perceptual or mentalistic; it seems like our general notion of matter is a set of properties like color, occupying some sort of physical space. If so, what do we have when we take away these perceptual qualities? Is our conception of physical matter really so vacuous?

On the other hand, Ken wants to insist that surely here is something outside us to be behind our perceptions. If all entities are mental, how can we think about entities we do not know about? What about entities that we only discover through the use of reason and science? What about events in the future? Can these strong willed philosophers ever agree? You’d better listen to the show to find out!

• Roving Philosophical Report(第6章42节):Zoe Coreneli插话了一篇关于尖端假肢的文章。义肢和大脑到底有什么关系?斯坦福大学的一个研究小组正在开发一种机器人义肢，它能够读取神经信号并将其转化为义肢的运动。有一天，这项技术将使我们能够控制电脑屏幕上的诅咒者，从而使瘫痪的病人能够像任何人一样通过电脑与外界交流。这项研究提出了关于我们是谁的深刻问题。我们只是神经元的集合吗?还有什么?你还记得《星际迷航》里外星人绑架斯波克的大脑来控制一个星球的那一集吗?-这能告诉我们我们是谁吗?

• Conundrum(seek to 46:56): Do copyright laws apply to graffiti? We’re not lawyers, but we doubt it. More interestingly, though—should they? Copyright laws are there to protect people’s ideas and creations, but what if these creations are illegal to begin with? Should we legitimize illegal creations to the same extent as legal ones, if at all?