Shakespeare’s plays, Einstein’s theories — and porn queen Jenna Jameson’s steamy online sexcapades.

New Yorkers can take their pick at the city’s public libraries, thanks to a policy that gives adults the most uncensored access to extreme, hard-core Internet smut this side of the old Times Square.

The electronic smut falls under the heading of free speech and the protection of the First Amendment, library officials say.

“Customers can watch whatever they want on the computer,” said Brooklyn Public Library spokeswoman Malika Granville, describing the anything-goes philosophy that’s the rule at the city’s 200-plus branches.

And that has religious leaders and library patrons — even some librarians — hotter than an XXX flick.

“What they’re doing is publicly funding an appetite for the most debased fare available,” said Catholic League President Bill Donohue. “It’s not like a Playboy centerfold anymore — it’s far worse.”

Library patron Daisy Nazario, 60, said she was grossed out when she discovered she was sitting next to an elderly porn watcher in the Brooklyn Central Library recently.

The looker was using library-provided extensions on the sides of his computer to block the view of his screen — which was featuring a threesome at the time — “but I could still hear the voices,” a disgusted Nazario said.

“It is very disrespectful to the children.”

Approached by The Post, the dirty old man skulked away, saying, “I don’t want to talk to you. Leave me alone.”

Under US law, all libraries that take federal funding only must install filters on publicly used computers to block content containing illegal obscenity and child pornography, and New York City officials say they comply to the letter.

If localities want to further restrict viewing, they must specifically enact a policy, although the move almost certainly brings with it legal challenges.

But even with the filters, anyone 17 or older can turn them off and troll for whatever sexual content floats their boat — no matter how deviant.

“The library cannot and does not guarantee that the filtering software will block all obscenity, child pornography or materials that are harmful to minors,” the policy says.

Library officials and civil libertarians say it’s a free-speech issue.

“In deference to the First Amendment protecting freedom of speech, the New York Public Library cannot prevent adult patrons from accessing adult content that is legal,” said New York Public Library spokeswoman Angela Montefinise.

douglas.montero@nypost.com

