Thank you all for these replies, I'll go on to dig into Bitcoin and Blockchain technology in general beacause this is really interesting !

Thanks for your replies guys, I'm starting to understand better.

So basically, dishonest nodes are not really a problem as long as it exists honest nodes and full nodes to verify the transactions.

But then is it possible to corrupt the blockchain by having a majority of dishonest nodes and full nodes ?

I see there are currently about 14 000 bitcoin nodes, would it be possible for a governement or other entity to create let's say 15 000 nodes (including full nodes) and then corrupt the network this way ?

Hi, I'm a complete noob and I start doing my researches about Bitcoin. The answer to my question is probably so obvious that it appears nobody really talk about it...

Why a Bitcoin node should be validing a transaction honestly ?

I mean, if I understand correctly, there are the miners who create the new blocs and the nodes who verify the transactions. But why should a node be honest ? What's the rewards for that ? Are all the nodes receiving a tiny fraction of the bitcoins which afterwards come to the miner's pocket or something similar ?

Thank you for your attention.