Did Heinlein intend to portray men and women as equals?

Spider Robinson gave an interesting answer to this question some years ago. He pointed out that Heinlein's women were often more intelligent and capable than the men, and that they were self confident enough to be willing to stoop to help out the coarser, dumber men in their lives so that they too could feel some achievement. On the surface it appears to be woman as subservient but in actuality they are in control and allowing themselves to be put in this role because they know how fragile are the egos of the men in their lives. I'm not sure if I am describing this well. The idea is that women are far more capable than men and allow men to indulge in their fantasy of being the strong manly man in order to preserve their delicate sense of self confidence.

I would say that isn't entirely unreasonable as an interpretation when his mid to late books all essentially had himself as the main character and Ginny as the love interest. Note that we generally (though by no means exclusively- see The Number of the Beast) see the female main character through the eyes of the male main character. That includes the male main character's interpretation of "well, you know how women get to be." But there are also hints that the male character doesn't actually realize how obtuse he is being. Sometimes the male protagonist will override the female protagonist's advice to their mutual detriment, and end up apologizing for being so stupid. At which point he is inevitably forgiven (see preserving his delicate self esteem, above).

However, I don't think this is always accurate by any means, particularly in his early-mid and early works. Again, there are absolutely exceptions to this. Sometimes you'll also see very capable women who are overwhelmed by emotion like heartbreak (Double Star) or who are simply in a place that they are denied the freedom to be able to plan or act effectively (Barbara in Farnham's Freehold). That doesn't seem to me to be set up as a slur against women so much as we all have times when we are overwhelmed with emotion or in a place that we have to take a back seat to someone else, and it doesn't make us any lesser of a person.

Sometimes the incredibly capable women are villainous (The Door Into Summer) and sometimes not (too many examples). Sometimes Heinlein will feature a stronger independent woman in the same story as a more traditionally depicted woman (although again they may be quite intelligent but just can't be bothered) to act as contrast but also to show that people are just different, and can change as they age. Grace Farnham, something of an antagonist in Farnham's Freehold, is described as having once been unbelievably strong, capable, intelligent, hardworking, supportive, but that years and decades of loneliness and indulgence had transformed her. And we see this to be true to a degree as well, when the babies are on the way and Grace has begun to transform into her old self. Then, when horrible stress and tragedy strikes, she retreats into delusion.

The only really naive, incapable female character I can think of was Sister Judith (thanks Lorendiac!) from Revolt in 2100, the Vestal Virgin for the Prophet. However, and this is important, the male protagonist was depicted as equally naive but having been at least somewhat trained. And again this was a situation where her character was held in contrast to more capable women in the story.

I've heard women defend both perspectives over the years. Some found Heinlein's women inspirational and went out into the world to kick ass and take names. Others liked the story okay but couldn't get past how they felt the women were depicted. They also went on the take on the world.

I'm a scientist, not a litterateur and have been informed over the years that even though a particular kind of interpretation is obviously ridiculous on the face of it and clearly not the intention of the author (ever hear Bradbury's fury over everyone teaching Fahrenheit 451 as a book about censorship?), because it is a defined form of interpretation, it is just as valid as any other. If that is the case, then I would think it equally applies to this question which seems to polarize people.

So you read the books the way you want, and if you enjoy them, great, and if you don't, that's also fine. Nobody loves everything.

As noted in the question, Heinlein's writing career was long and started a very long time ago (1939-1987). This is a man who was born in the Bible Belt in 1907 and spent the first half of his life vigorously interrogating his own upbringing and coming to radically different conclusions about ethics and religion than the conventional wisdom of his native time and place. He had a considerable stylistic range and wrote on many different themes for some very different audiences.

As background, Heinlein was a socialist in the 30's, while later in life he tended to express libertarian views. His wife Ginny was a biochemist and a navy (WAVES) veteran. There is a story that when he was used on TV as a color commentator during the Apollo program, he flustered Walter Cronkite by suggesting that women should be allowed to be astronauts. However, his views with respect to feminism and women's roles were certainly not PC by modern standards.

Early career, 1939-1947

Heinlein's fiction from this period shows him still working on putting together his style, with some of his work such as For Us, The Living and Rocket Ship Galileo being noticeably below his later level of proficiency. This period provides the best ammunition for those who want to portray Heinlein as racist and misogynistic.

In 1941, he published two novellas in Astounding, "Universe" and "Common Sense," which were later combined into a fix-up novel called Orphans of the Sky. They depict a society aboard a generation starship that has degenerated into ignorance, superstition, cannibalism, and slavery. Slavery includes all or nearly all women, who are treated as chattels, are named by their men, and are subject to casual physical abuse. (There is one female character, a knife maker, who lives independently and is afforded some respect because her craft is important, but she is beaten down by one of the sympathetic male lead characters when she attempts to stand up to him.) Whereas the other negative aspects of this society are treated very creatively, from multiple angles, and in considerable depth (e.g., a sympathetic character narrowly avoids being eaten), this is not so for its misgyny. Author Amal El-Mohtar writes that the book is:

often interesting, and competently written, except for the bit where every aspect of this society's ignorance is complicated and problematized and addressed -- except for the women-are-silent-chattel aspect, which up until the very last page of the novel, is taken as read.

If anything, I think she understates the problem with this particular work. Reading it, I get a disturbing feeling that violent subjugation of women is supposed to be a joke, for the amusement of male readers.

Orphans of the Sky does, however, seem to me to be completely atypical of Heinlein's treatment of women, even in this early period, when he was already showing considerable creativity in his treatment of gender roles. For example, there is a scene in the 1942 Beyond This Horizon in which two male characters compare notes on their badass firearms, after which one of them compliments the other on the shade of his nail polish.

Maturing style, 1947-1958

Toward the end of the 1940's, Heinlein broke away from the stereotyped pulp fiction style and became the first science fiction author to sell stories to the "slick" magazines such as the Saturday Evening Post. A big chunk of his writing during this period was his juvenile novels, many of which were serialized in the Boy Scouts magazine Boy's Life before being published as books. These are written for a nominal audience of teenage boys (although Heinlein prided himself on not talking down to his audience, and fought a running battle with his prudish editor over their contents). In some of these, girls and women are simply absent. One (Podkayne of Mars) has a female lead who is somewhat saintly and has a younger brother who [spoiler 1]

In several of the juveniles, there is the theme of the boy protagonist who is forthright and courageous but not terribly bright, and has to be helped by a more intelligent and sophisticated girl (The Star Beast, Have Space Suit--Will Travel). In Starship Troopers (originally submitted to his publishers as a juvenile), the protagonist ends up as a grunt in the interstellar marines because he isn't as good at math and electronics as his high school friends, but one of the women his age becomes a starship pilot. In two of the juveniles [spoiler 2] there is a surprise revelation that a character thought to be one sex is actually the another.

One of the juvenile novels (The Rolling Stones) features a cantankerous, hypercompetent grandmother who is an experienced spaceship pilot. In Starman Jones the teenage female lead hides her intelligence until it is revealed later, and in The Star Beast she sexually manipulates an older man (or tries to?) to humorous effect.

Mature style, 1958-1969

In Heinlein's books for mature audiences from before 1970, we see some of the same shticks, such as the confused or less intelligent man paired with the more experienced and intelligent woman (Glory Road, For Us The Living), and the hypercompetent woman (Glory Road, Barbara in Farnham's Freehold). In Stranger in a Strange Land, the protagonist manipulates his own sexual biology to give himself an androgynous body. In another of his works from this period, when he was at the peak of his powers, the computer in The Moon is a Harsh Mistress consciously switches back and forth between being psychologically male and female.

Late works

Later in life, Heinlein ran into a series of health challenges that he feared had clouded his thinking, and he began to doubt his own ability as a writer. Around this time, he stopped accepting requests for revisions from editors, and started getting feedback mainly from his wife, Ginny. My judgment is that his writing from this period is almost all awful, but others disagree.

One of the standard critical complaints about his novels from this period is that the characters are one-dimensional and not believable, and I think this applied to both his men and his women. Cases in point are the sexy madonnas of I Will Fear No Evil and Time Enough for Love. Even more cringeworthy is Deety in The Number of the Beast, who spends a lot of time thinking about how happy she is that her husband likes her big breasts. Friday, one of his stronger works from this period, has a female protagonist who is an artificial person and disbelieves her own self-worth, although the narratives show her to be a superior person in various ways. To Sail Beyond the Sunset features a female POV who is filled in from her sexy madonna depiction in earlier books.

Another common criticism of this period is that Heinlein often uses characters as mouthpieces for his own opinions. This is more frequently done with male mouthpieces, but there are female examples (Maureen in To Sail Beyond the Sunset, two of the POVs in The Number of the Beast). (Something similar, although less overt, happens in the earlier Glory Road, where the female lead Star voices Heinlein's political opinions.)

One thing to keep in mind while putting all of this in perspective is that during most of Heinlein's early writing career, he was unusual among SF writers simply for writing fleshed-out characters at all. He made much more sophisticated use of voice and point of view than his peers in the "big three" Clarke and Asimov.

Spoiler 1:

Spoiler 2:

I was searching around for some well-cited academic analysis and/or non-fiction Heinlein might have written that could clarify his intentions and beliefs relevant to feminist criticism and came upon a similar question, which I participated in, but was later closed for what I felt were pedantic reasons. So I created this new question that would hopefully be able to remain open and represent the topic in a more useful way over time. (And I have finally moved and tweaked the last version of my answer.)

Introduction

People sometimes say that "Heinlein's women are basically men," but Heinlein repeatedly emphasizes in much of his fiction that men and women are innately, categorically limited by and different in the workings of their minds and emotions due to their biological sex. The TL;DR is that, despite portraying intelligent, empowered, professional women, Heinlein also frequently depicted differentiation between men and women and reasoning for it "suspiciously similar" to traditional sexism.

Digressing momentarily to my opinion, I don't have strong opinions about whether Heinlein or his work were feminist or sexist. I suspect the answer for both is both. To whatever extent that Heinlein's portrayals of people (men, women, etc.) are are realistic or positive, it isn't due to deeply nuanced characterization or a total absence of stereotypes. Heinlein's work often has the feel of ideas explored abstractly--not entirely impersonally, but the focus is not on characterization, feelings, or perspective. My summary would be that Heinlein's narratives seem to say that many hallmarks of traditional gender roles are due to biology as destiny. But the bottom line also seems to be, "So what?! If men can work, invent, govern, and fight under the influence of their hormones, so can women." This is not a bad message, so my overall feelings on the matter are nuanced.

Assuming that is Heinlein's message, that is. It's not clear if the gender essentialism in Heinlein's characters and plots comes from a traditionally sexist mindset, or if it was meant to cater to it, or maybe meant to say that different people will naturally have different perspectives and that their sex will influence those perspectives. Meaning is hard to pin down, thus my interest in Heinlein's own takes on his own meaning.

However, my perception is that (in most of of the articles and conversations I've read) Heinlein's "defenders" tend to give more detail than his "detractors." So, despite not having overwhelmingly negative feelings myself, I have made an effort here to fill in the gaps regarding how sexism does appear in Heinlein's work.

Sexist Memes in Heinlein

The following are canonical examples of "suspicious" portions that could appear to be sexist (and mostly, I think, disprove that "his women are basically men"). There are vague spoilers throughout. The majority cite narration, plot events, or dialog. The last cites a letter Heinlein wrote to a publisher. I haven't read as much of Heinlein's YA; maybe check out Heinlein's Female Troubles, which focuses on his YA.

• His characters do suggest that sex affects the work women are fit for in less civilized societies--for their own good, of course--and aren't always "proven wrong." (Farnham's Freehold, The Number of the Beast, Time Enough for Love). Traditional sexist memes invoked: "Nature over nurture" and "Women need to be protected."

• Also it is clear that, in Heinlein novels, all women are "naturally" inclined to desire children and to nurture them, unless they have been traumatized (Friday, Stranger in a Strange Land, Podkayne of Mars). Traditional sexist meme invoked: "Women are naturally maternal."

• He wrote a couple of women who said that women get the most horny when they think about pregnancy and enjoy sex the most when pregnancy is a possibility (To Sail Beyond the Sunset, I Will Fear No Evil). Traditional sexist meme invoked: "Women's sexuality has ulterior motives."

• Plot events suggest that women are so overwhelmingly attracted to powerful men that, without regard to their partners' feelings, they will deliberately seek out and nurture cuckoo's eggs if a sufficiently desirable mate appears (To Sail Beyond the Sunset, Time Enough for Love). Traditional sexist memes invoked: "Women will trade up to more powerful caregivers" and "Women are faithless."

• Some characters seem to support the notion that the most feminine women are frequently a little vapid--although the justification might be their preoccupation with the very serious matter of creating the next generation (Stranger in a Strange Land, Number of the Beast). Traditional sexist meme invoked: "Women are silly."

• Several women narrate that they are smart: smart enough to realize that, as women, it doesn't best serve them to flaunt their intelligence. Instead, they can deliberately let men think they are stupid and benefit from this because the men will do things for them while simultaneously underestimating them (To Sail Beyond the Sunset, Podkayne of Mars, Friday). Traditional sexist memes invoked: "Women are manipulative" and "Women use sex against men."

• He writes of much older men who are attracted to barely pubescent girls (and vice versa) and implies via narration that this is very natural on both ends. Compounding this, girls as young as 12 are implied to have sufficient maturity to pursue this choice. How? The girls come back few years older and get laid (The Cat Who Walks Through Walls, To Sail Beyond the Sunset, Time Enough for Love). Traditional sexist memes invoked: "Men are way into young girls, but why shouldn't they be when the young girls pursue them" and "Women mature faster than men."

• One novel suggests post-menopause is the best time to seek a career for women (To Sail Beyond the Sunset), since they no longer have better things to do. Traditional sexist meme invoked: "Building a family is the dream for women". Remember, in traditional sexist stereotyping, babies are always the most important thing for women. They are (or, one supposes, should be) important for men too, as members of the human species--but are so much more especially important for women that women can't/shouldn't/won't do anything else.

• One narrative justifies a character abandoning his wife of many decades--in the process attempting to deprive his children and ex-wife of the vast majority of their communal money and property in favor of his new, young wife and his new stepchildren--on the rationale that he's just doing his duty by his new wife (To Sail Beyond the Sunset). Traditional meme invoked: "The domestic/caregiving role has no value compared to breadwinning."

• Some of his female characters judge others who do not conform (especially to the obsession with motherhood), implying that all right-thinking, truly feminine women will sympathize and agree with their perspective--that any who don't are unnatural and unfeminine (To Sail Beyond the Sunset, I Will Fear No Evil). Traditional sexist meme invoked: "Women are catty."

• At least one of Heinlein's juveniles, if you take Heinlein's own word in a letter to his editor, may be a parable for mothers who focus too much on their careers and too little on their children (Podkayne of Mars). Unless he was being sarcastic in the letter...dot dot dot. Traditional sexist meme invoked: "Bad mothers are ruining the world."

Most of these appeared in multiple novels, but they only scratch the surface of Friday and I Will Fear No Evil.

SPOILERS for Friday

There is a notorious rape in Friday. She does literally say that the best option for a rape victim is to try to enjoy it. On the other hand, she indicates that it's more pretending, says she can consider this because she is trained, and that it is a psychological tactic to lower her rapists' guard to aid her escape. On the other other hand, she also mentions finding one of the rapists almost pleasant and later marries him. On the other other other hand, she kicks his ass first and makes him admit to his crime (although OOOOH his apparently genuine remorse is overshadowed by, "you were so sexy I couldn't help it").

END SPOILERS for Friday

SPOILERS for I Will Fear No Evil

There are definitely some creepy overtones and unpleasant implications in the events of I Will Fear No Evil. To wit, an old man's brain gets transplanted into his beautiful young secretary's body: her body is now literally his and yet she's still in it. Her personality lingers in the body with awareness. She cedes control to him, however. Over time, the sex of his body changes how he thinks and feels: he becomes she. In some cases, what would have been offensive to him as a man became acceptable to her as a woman--even being talked down to and sexually harassed.

END SPOILERS for I Will Fear No Evil

On a closely related note, there are also noteworthy things in Heinlein's treatment of LGBTQIA+ characters. For example, he portrays homosensuality positively (Galahad, Mike the Martian), but wrote at least a couple scornful asides about homosexuality. Also, he portrays a certain amount of gender fluidity positively (Mike the Computer, Joanne Eunice, Slipstick Libby), but also seems to say it's dysfunctional if one's behavior doesn't match relatively traditional behavior deemed appropriate for one's sex.

Conclusion

I hope my examples show that Heinlein's work can come off as regressive today for good reasons. Still, I want to emphasize that I do personally think any writeoff of Heinlein's writing as bad for/at women is as inaccurate as any vaunting of it as great for/at women. As I think the Friday spoiler especially shows, even a single topic can have details that point both ways.

As to the man himself, there's no doubt that some of the ideas he explores were ones he agreed with, but it's not clear from the novels alone which ones.