他有三寸不烂之舌，几乎没人能驳倒他。

He has a glib tongue. Few people can argue him down.

不过，大滞胀的观点也不能完全驳倒。

And yet the idea of a great stagnation cannot be dismissed entirely.

我回嘴，指着我明摆着的紫斑作为见证来驳倒她。

I retorted, showing a decided purple witness to refute her.

我们当然有了一个迹象；但即使该命题为真，该论述也是可以驳倒的，因为它并没有形成三段论。

Here we certainly have a Sign; but even though the proposition be true, the argument is refutable, since it does not form a syllogism.