Love. Rand's most sophisticated theory of love appears in The Romantic Manifesto:
Love is a response to values. It is with a person’s sense of life that one falls in love—with that essential sum, that fundamental stand or way of facing existence, which is the essence of a personality. One falls in love with the embodiment of the values that formed a person’s character, which are reflected in his widest goals or smallest gestures, which create the style of his soul—the individual style of a unique, unrepeatable, irreplaceable consciousness. It is one’s own sense of life that acts as the selector, and responds to what it recognizes as one’s own basic values in the person of another. It is not a matter of professed convictions (though these are not irrelevant); it is a matter of much more profound, conscious and subconscious harmony.
Many errors and tragic disillusionments are possible in this process of emotional recognition, since a sense of life, by itself, is not a reliable cognitive guide. And if there are degrees of evil, then one of the most evil consequences of mysticism—in terms of human suffering—is the belief that love is a matter of “the heart,” not the mind, that love is an emotion independent of reason, that love is blind and impervious to the power of philosophy. Love is the expression of philosophy—of a subconscious philosophical sum—and, perhaps, no other aspect of human existence needs the conscious power of philosophy quite so desperately. When that power is called upon to verify and support an emotional appraisal, when love is a conscious integration of reason and emotion, of mind and values, then—and only then—it is the greatest reward of man’s life.
Because many men and women nowadays seek sexual partners who share common interests, Rand's account of love, at least on superficial acquaintence, may appear to have an aura of plausibility around it. However, Rand's theory of romantic love relies very heavily on her theory of emotions and her belief in a "conscious intregration of reason and emotion." Neither of these theories can boast a particularly strong accordance with reality. Since emotions are not automatized value judgments, but are rather at least partially the result of innate inclinations; and since, moreover, the perfect integration of "reason and emotion" is impossible due to the fact that the brain is made up of competing subsystems; and since, most importantly of all, men and women are innately different: all these facts stand in the way and prevent Rand's ideals about love from ever being fully realized. How love actually works in the real world is somewhat different than how Rand imagined (or perhaps desired) that it should work. Common interests may be a component in romantic love; but the notion that an individual falls in love primarily with a "sense of life" does not really accord either with common experience or scientific evidence.
Love, just like sex, has a biological foundation which Rand tends to ignore. As the David Desteno and Piercarlo Valdesolo, authors of Out of Character, contend:
...romantic love actually helps us solve an important evolutionary problem. How do you know your partner will remain committed to you and your children (and you will remain committed to her or him) in the face of constant temptation? How do you ensure he or she won't run off with the sexy tennis pro, leaving the kids vulnerable and unprovided for? Love, for lack of a better phrase, is the answer...
Several studies have found a reliable link between a man's level of testerone and mating effort; the higher the testerone, the more effort expended not only in finding a mate but also in competing with rivals for her affection. On the flip side, studies have also found that once a man is in a committed relationship, lower testerone is associated with monogamy. In one, Matthew McIntrye and colleagues measured the testerone levels of men in committed relationships and then had them report their interest in having sex with other women. As it turned out, those with higher testerone levels reported having more interest in playing the filed, while those with relatively lower levels were more comfortable with commitment... And because, as we've noted, women are so adept at (subconsciously) picking up subtle cues that signal high testerone, this can be a good marker of whether that guy across the room is Mr. Right or Mr. Right Now. [75-76]
Rand's "sense of life" construct can in some ways can be regarded as an attempt to explain, on the basis of her own philosophy, the "subtle cues" that trigger love interest. The problem is that individuals aren't really capable of having the sort of consistent sense of life that Rand takes to be an ideal, precisely because the mind doesn't work that way. Furthermore, the emotional system, precisely because it relies on a very complex interaction of partially innate predispositions and "acquired" dispositions, does not easily fit a simple category such as Rand's "benovelent" sense of life.
Yet this barely scratches the surface with what is wrong with Rand's approach on this issue. In practical terms, Rand's sense of life manifests itself as various emotional responses to works of art. Presumably, therefore, if one falls in love with a person's sense of life, one is falling in love with their emotional responses to works of art. We would expect, then, to find in long-term love relationships a very strong correlation in the aesthetic tastes and evaluations of the romantic couple. Such strong correlations are rarely found in common experience; nor has scientific research been able to find evidence of them. What we find, instead, is that couples in long-term relationships feel the same or similar about some things, and different about many others. The near complete unity in aesthetic evaluations envisioned by Rand is rare and unnecessary for love to flourish and last.
Rand's view of romantic love, due to its fanciful character, is potentially mischievous and destructive. It posits a false ideal which, if followed with intransigence, can lead to trouble. Since men and women are, in many ways, very different, it is unlikely that a given individual is will actually run across someone of the other gender complete (or even nearly complete) unanimity of professed and subconscious convictions. And those who insist on nothing less than a "conscious and subconscious harmony" with their love interest will probably spend their life alone, as such a person almost certainly doesn't exist.
Furthermore, there exists no evidence that an individual's sense of life is in fact indicative of monogamous inclinations. Yet, from a biological perspective, that would appear to be the functional basis of love. The world must be peopled. Sex and love appear to have arisen with the human psyche primarily for the purposes of reproduction. The fact that Rand completley ignores this side of the issue in her account of love tells us more about Rand herself than it does about the role love plays in the lives of most human beings.