Reasonable Humans and Animals

Here is a crisp (but badly edited) essay by philosopher Nathan Nobis. I like Nathan's distinction between "Oh yeah?" and "So what!" as replies to an argument. Suppose you claim that proposition C follows, logically, from propositions P1 and P2. There are two mistakes you can be making. First, one or more of your premises may be false. Second, your conclusion may not follow, logically, from your premises, even if the premises are true. If I reject one of your premises, I'm saying, in effect, "Oh yeah?" If I deny that your conclusion follows from your premises, I'm saying, in effect, "So what (if your premises are true)!"