It's broad in the human (as opposed to Heinlein's Martian) sense because we engage with religion, philosophy, and science in a largely intellectual way. Yes, even wingnut fundamentalists. They're all highly linguistic things; most of our more mystical traditions have fallen by the wayside for one reason or another.
In the Martian sense, that mystical perspective is far more useful: it unifies their physical reality of transcendent Old Ones and life that can be grown through singing and so on. The presence of a single word signals that they've collapsed all of these things down to a simple concept; the lack of a human analog simply says we haven't.
So to make a long thing short, the word cuts to the heart of a conceptual area that we can but dance around with all of our words and qualifications and half-understandings in the fields of religion, philosophy, and science. The desire to know divinity, to know oneself, to know the universe: these can be streamlined into a single concept, to grok.
Thus why Heinlein goes on to have Mike explain his pantheistic "God is that which groks". The closest English word I know of is not "understand" but rather "suffuse" or "permeate". To me, the reason the word survives the novel as a mere stronger version of "understand" is because most people hand-waved the novel's walk-through of religion as a boisterous critique rather than as a considered and valid approach to life, the universe, and everything.
It's broad in the human (as opposed to Heinlein's Martian) sense because we engage with religion, philosophy, and science in a largely intellectual way. Yes, even wingnut fundamentalists. They're all highly linguistic things; most of our more mystical traditions have fallen by the wayside for one reason or another.
In the Martian sense, that mystical perspective is far more useful: it unifies their physical reality of transcendent Old Ones and life that can be grown through singing and so on. The presence of a single word signals that they've collapsed all of these things down to a simple concept; the lack of a human analog simply says we haven't.
So to make a long thing short, the word cuts to the heart of a conceptual area that we can but dance around with all of our words and qualifications and half-understandings in the fields of religion, philosophy, and science. The desire to know divinity, to know oneself, to know the universe: these can be streamlined into a single concept, to grok.
Thus why Heinlein goes on to have Mike explain his pantheistic "God is that which groks". The closest English word I know of is not "understand" but rather "suffuse" or "permeate". To me, the reason the word survives the novel as a mere stronger version of "understand" is because most people hand-waved the novel's walk-through of religion as a boisterous critique rather than as a considered and valid approach to life, the universe, and everything.