This is laughably wrong. Aristophanes wrote an entire comedy on the subject, "The Clouds", in the 5th century B.C.E.
STREPSIADES: But by the Earth! is our father, Zeus, the Olympian, not a god? SOCRATES: Zeus! what Zeus! Are you mad? There is no Zeus. STREPSIADS: What are you saying now? Who causes the rain to fall? Answer me that1 SOCRATES: Why, these, and I will prove it. Have you ever seen it raining without clouds? Let Zeus then cause rain with a clear sky and without their presence! STREPSIADES: By Apollo! that is powerfully argued! For my own part, I always thought it was Zeus pissing into a sieve. But tell me, who is it makes the thunder, which I so much dread? SOCRATES: These, when they roll one over the other. STRESIADES: But how can that be? you most daring among men! SOCRATES: Being full of water, and forced to move along, they are of necessity precipitated in rain, being fully distended with moisture from the regions where they have been floating; hence they bump each other heavily and burst with great noise. STREPSIADES: But is it not Zeus who forces them to move? SOCRATES: Not at all; it's the aerial Whirlwind. STREPSIADES: The Whirlwind! ah! I did not know that. So Zeus, it seems, has no existence, and its the Whirlwind that reigns in his stead? But you have not yet told me what makes the roll of the thunder? SOCRATES: Have you not understood me then? I tell you, that the Clouds, when full of rain, bump against one another, and that, being inordinately swollen out, they burst with a great noise. STREPSIADES: How can you make me credit that? SOCRATES: Take yourself as an example. When you have heartily gorged on stew at the Panathenaea, you get throes of stomach-ache and then suddenly your belly resounds with prolonged rumbling. STREPSIADES:
Yes, yes, by Apollo I suffer, I get colic, then the stew sets to rumbling like thunder and finally bursts forth with a terrific noise. At first, it's but a little gurgling pappax, pappax! then it increases, papapappax! and when I take my crap, why, it's thunder indeed, papapappax! pappax!! papapappax!!! just like the clouds.
SOCRATES:
Well then, reflect what a noise is produced by your belly, which is but small. Shall not the air, which is boundless, produce these mighty claps of thunder? STREPSIADES:
And this is why the names are so much alike: crap and clap. But tell me this. Whence comes the lightning, the dazzling flame, which at times consumes the man it strikes, at others hardly singes him. Is it not plain, that Zeus is hurling it at the perjurers?