Laughter a bad criterion for falsification

I enjoyed reading this neat little dig at Giordano Bruno, and Leibniz, via a deft thumbnail of The Entirety Of Western Thought:

His [Bruno's] metaphysics seems to me about as diametrically opposed to the truth as possible (for realists, that is; correlationism is much worse). But he’s always a pleasure to read.

There’s also one example of archaic backsliding in his metaphysics– his assumption that something must be permanent to count as substance. One of the highlights of Aristotle compared with earlier Greek thinkers was his breaking of the link between substantiality and permanence. In fact, this link is perhaps the most regrettable feature of all the pre-Socratics as well as Plato. Aristotle broke it. Bruno’s back with it, as are Descartes, Spinoza, and (unfortunately) Leibniz.

Bruno wasn’t the first to backslide on it, of course. Most of Christian philosophy and neo-Platonism did the same thing. But point your finger at “natural kinds” in Aristotle all you like; at least he lets individual frogs and trees be substances without having to last forever. Bruno blows that sky high, and Leibniz too, but even more comically so (dead animals still live somewhere, invisible, attached to tiny bodies).

Permanence: a bad criterion for substance.

Hard to disagree, of course. But what interests me is the (attractive enough) slippage into ridicule, the 'dead animals still live somewhere, invisible, attached to tiny bodies' and so on ... there's a problem there. I take it the logic is: you can see how wrong this is beause it's ridiculous!' The ambiguity in that last word isn't helpful, I think. If we mean 'ridiculous' in the modern sense of 'no serious person could believe this' then the statement is tautological. If we mean it in a stricter sense, 'this thing you believe is laughable' ... well, being comical isn't incompatible with being true. Plenty of comical things are true. Indeed, Freud might argue that laughter is precisely an index of truth, albeit a truth our conscious minds are disinclined to acknowledge. The danger is invoking the second of these meanings pretending it's the first. I can believe that permanence is a bad criterion for substance: but I don't see that 'permanence is a bad criterion for substance because the very idea makes me laugh' is good argufying.