He lived 2 centuries before Newton, 3 centuries before Laplace, 4 centuries before Maxwell and 5 centuries before Noether, Einstein, and Shannon. That he doesn't believe the first law of thermodynamics is hardly his fault.

And all of those names effectively built on a foundation that Da Vinci helped establish. It wasn't modern science just yet but it was a massive step up from what came before.

And in a way that is probably his biggest contribution: to show that if science focuses on that which works and can be generalized there will be massive progress. Because for a single individual, especially in that age his output was extremely impressive and that couldn't have worked if he didn't channel his energy to areas that were deemed to be fruitful.

Well he lived before modern laws of physics were known… I'm not sure that counts.

Actually: he was instrumental in inspiring others to search for those modern laws of physics and at that point such experiments must have helped to figure out where exactly the line was culminating in the laws of thermodynamics.

The replies don't make a ton of sense, did you change the contents of your comment?

Yes, the comment was changed considerably. Originally it gave Leonardo Da Vinci's attempts to create a perpetual motion machine as an example of a smart and successful person falling for a dumb idea.

Even in the source it says he was against such ideas.

> Leonardo da Vinci made a number of drawings of devices he hoped would make free energy. Leonardo da Vinci was generally against such devices, but drew and examined numerous overbalanced wheels

Just drawing some stuff that looks like perpetual machine isn't the same as actually believing in it. In fact this is how science should work. Even if something has a small chance to be correct try that and think about it. Einstein didn't believed in black holes but thought about breakdown of his equations.

That source wasn't there in the first version.