Pointing out a seeming contradiction in an advocate's advocacy is not an ad hominem.

Having your central argument against his case focused on his personal contradiction, is:

  "That genie is out of the box, when you decided that you 
  didn't mind a company gatekeeping which software you can 
  install on "your" devices you opened that can of worms, the 
  one where any company can gatekeep anything they want as 
  long as it is "convenient" for most people."

Wikipedia agrees it's an ad hominen, but NOT fallacious (if true): "However, in some cases, ad hominem attacks can be non-fallacious; i.e., if the attack on the character of the person is directly tackling the argument itself. For example, if the truth of the argument relies on the truthfulness of the person making the argument—rather than known facts—then pointing out that the person has previously lied is not a fallacious argument." Lied and contradicted oneself are a close-enough match - but outright contradictions are rare; complex opinions and judgments common.

That central argument you're talking about doesn't look like it was aimed at Grubber's case. I don't see any disagreement with Gruber's post. I believe it's an attack against Gruber himself, that says the hypocritical bastard got it coming, and even shares some responsibility for advocating the brand that single handedly popularised that kind of lock down.

But rebutting an argument by attacking the character of the person making it, is.

Ad hominem attacks are considered logical fallacies only when they're used instead of a dismantling someone's arguments. If they're not making a sound argument at all, yet they continue to make it, there's no way to argue the argument, the problem is a character defect - so attacking the character of the person is logical in that case and accepted in debate.

Not all people are good. And not all smart people argue logically.

>Ad hominem attacks are considered logical fallacies only when they're used instead of a dismantling someone's arguments.

Which is precisely the case here.

I don't think he is arguing against independence for publication. He is instead arguing against the app store restrictions on account that they are equivalent. It is not illogical to point out an hypocrasy if the point is that his own arguments should be more broadly applied. The tone was unnecessarily ad hominem but not the overall argument.

Yeah, my comment was a bit more emotional than required and ended up sounding like an ad hominem, but the overall point was that people (not just the author of the piece) vote with their wallet, and they voted that gatekeeping is OK; mostly they have been showing that "convenient"=OK regardless of how many privacy issues it rises or how much free speech could be affected.

Still, I understand the point of those who consider news publishing independence to be more important than software publishing independence. But I think they may be missing the bit of irony (regardless of AMP) that Google is still the search engine they use to find those news, Google may as well delete a full domain from their search results and make a site disappear into oblivion. But at least Google-search has been forced -in some cases- to keep some level of neutrality there. Apple is just freely deleting and adding whatever they want to iOS/App-store, with some of their apps having access to APIs no other app can (e.g. Safari), which is as monopolistic as software gets.

But it could be an argument from fallacy. https://en.wikipedia.org/wiki/Argument_from_fallacy

You're correct, technically. It's "tu quoque", which is arguably a more forgivable fallacy.

It's tu quoque. Not much better.

>First of all, that's an ad hominem

Technically it's an argument from hypocrisy, more commonly known as "Tu Quoque".

Sorry, just get a bit anal about people confusing different fallacies because it makes it hard for some people to understand =P

Ad hominem arguments are chiefly problematic in pure logical discourse. In normal human rhetoric, the reputation of the person making the argument often factors in to whether listeners view the argument as truthful. It's not a problem to point out things that reduce the impact of reputation on rhetoric.

Essentially, any time a public figure says something, there's an implicit, "I have been truthful before, I am being truthful now," leading the statement. If someone's opinions are self-inconsistent, it's important to know that one can discount that implied statement.

> First of all, that's an ad hominem. If publication independence is important, then it remains important whether Gruber is hypocritical about it or not.

I agree! It's a poison in the well lazy people use to discredit something they don't like without thinking about it.

However, in this particular instance it raises questions of whether or not Gruber is arguing in good faith. It lends credence to accusations that editorial independence might not be his overriding concern.

No, it doesn't. I don't even understand why you're making such an argument. What exactly are you implying is his secret concern?