Conventional wisdom watch: Apple is doomed. Google is forever.

January 21, 2014, 9:34 PM UTC

Isaacson: Google is more innovative than Apple.

FORTUNE — There’s been a lot of commentary — good and bad — in the week since Google (GOOG) made its $3.2 billion bid for Tony Fadell’s Nest Labs.

Fadell was best known, before he moved into WiFi-connected appliances, for running Apple’s (AAPL) iPod division. So last week’s news naturally led to a conversation about Apple and Google and what — at its core — each company is about. (Our initial take: Why Google, not Apple, bought Nest.)

The remark that got the most play in the media was probably the least considered. Steve Jobs’ biographer Walter Isaacson, pressed on CNBC Thursday morning to comment on the two big news events of the week — the iPhone’s launch on China Mobile and Google’s purchase of Nest — casually remarked that “the greatest innovation in the world today right now” is coming not from Apple but from Google. That did not sit well with Apple aficionados. Headline on MacDailyNews: “Scribe of flavorless Steve Jobs biography thinks Google is ‘more innovative’ than Apple because Google bought a thermostat company.”

On Friday’s Accidental Tech Podcast John Siracusa offered what may be the most apocalyptic view. The risk, he said, is not that Google will do something more evil with data from inside your home than it does now with all the information it’s already collected from your gmail, your Android phone, your Google searches, your taste in YouTube videos etc. The real danger, he said, comes when the information about you in Google’s servers eventually, inevitably, falls into the hands of actual evil doers.

But the most thoughtful commentary came, as it often does, from Asymco‘s Horace Dediu.

Dediu, a student of Clayton Christensen‘s disruption theory, is always looking for the “why” of a company — its business model, its values, its guiding principles. Google is a tough nut to crack because its stated principle — “don’t do evil” — is too vague to be of any use, and its business model — selling advertising — is largely disconnected from what it is known for: Providing valuable Internet services for free.

For a lot of people, Dediu writes, Google is the Internet.

“We don’t question the survival of the Internet so we don’t question the survival of Google — its backbone, its index, and its pervasive ads which, somehow, keep the lights on. We believe Google is infrastructure. We don’t dwell on whether electric grids are vulnerable, or supplies of fuel, or the weather(!)”

Apple, in contrast, is always seen by Wall Street as “temporarily enjoying a stay of execution.” There is no “Google death knell counter,” he writes, as there is for Apple. There is no “Google is doomed” trope. 

“If an executive from Google quits or is fired there is no investor panic. If a product is withdrawn there is no mourning. There are no journalists pursuing Pulitzer prizes by describing some seamy underside of Google.”

Google, he writes, is viewed as a system, owned and run as a public good by a benevolent triumvirate (Larry Page, Sergei Brin, Eric Schmidt). Apple might also be viewed as a system — as a perpetual disruption machine, perhaps — but that’s not the conventional wisdom.

“Because [Apple is] not a system,” Dediu concludes, “it’s fragile. It’s a person, or an idea, or a product or a singular ‘key’ to something. It is, ultimately, mortal. The only debate is when it will die and points are earned for calling it sooner rather than later.

“But what if Apple were a system? And what if Google were a person (or three?)”

Now those aren’t questions likely to get asked — or answered — on CNBC.

UPDATE: Dediu dives even deeper into Google’s raison d’être in Wednesday’s Critical Path podcast: Episode 109: Google Ventures.