Equality is far from achieved, even now, and many women will be conscious at some level of how the patriarchy still affects their lives. The feminists who campaigned against sexual oppression held the view that the relationship between the penis and the vagina was symbolic of the tension between men and women in society - that it was a political object, one which represented the dominance of men over women, and that the very act of penile penetration was symbolic of male power penetrating female passivity at the behest and whim of the man, while the woman had to passively accept this. Obviously this is an attack upon heterosexuality, seeing it as equivalent to male patriarchy, but it sees to me it is also an attack upon women's power, and defines them as inherently powerless people.

As time went by the argument became more refined, and the focus of the argument became the penis. Regardless of the fact that women seem to like penises, and playing with them, the feminists began to question whether the penis was actually an object with the power to keep women in a subjugated role: rather like the argument that Freud was trying to oppress women by declaring the only good orgasm was a clitoral orgasm. In reality a clitoral orgasm is in fact the way most women reach orgasm, and the fact that it is independent of the penis thrusting during intercourse appears to be more of an unfortunate design fault than a concerted attempt by men to keep women in their place by depriving them of orgasm.

The argument is infinitely extendable, in the sense that any association of sex and sexuality can be politicised. So the pill, far from being a liberating force for women who had the freedom to control the birth rate, became an enemy of the patriarchy, something which liberated women from the tyranny of the ever-ready, rampant and controlling penis.

Inevitably, feminism became diluted and more in tune with normal women's views. The de-politicizing of feminism was advanced by Shere Hite's ahead-of-its-time report on female sexuality, which served to dispel the illusions of women who may have believed that they were sexually inadequate in some way. For example, those who believed they were failures because they did not have vaginal orgasm on demand were relieved to find that very few women (in fact almost none) reach orgasm in this way.

Rape, too, can also be thought of with reference to sexual politics. In such a scenario, a man's ability to penetrate his partner's (or any woman's) body even if she was unwilling for this to happen can be seen as the ultimate sign of a man's higher strength, the ultimate symbol and weapon of his masculinity and manhood. "Man's amazing discovery that his sexual organ - his penis - was well able to serve as some kind of weapon seems to rank as a most important discovery - one of the significant discoveries of prehistory," wrote one female observer (I have paraphrased). But there are a lot of problems and objections to this reasoning. For example, rape is not universal - in some cultures it hardly exists. Also, rape has been depicted by some scientists as an evolutionarily motivated attempt to fulfill a biological urge to reproduce by males who are so inadequate that they have no other way of mating. This may have a degree of truth in it.

So as you can see there are many different ways of looking at this. Perhaps inevitably, scientists have started to look at the levels of testosterone and arousal that men experience in various sexual situations. The idea of this is to try and establish whether or not there is a connection between masculinity in any form and sexual violence. Suppose for example that a normal man becomes aroused when he's shown images of rape and other sexually violent acts. What would be the implication of that? Does it give support to the feminist idea that "all men are rapists"? It's clearly an important question, and anything that can throw light on the subject will be of value.

So in one study, marred by controversy for several reasons, a psychologist at the UCLA showed a group of college students two films, one showing consensual sex, and the other showing nonconsensual sex. According to the device attached to the students' penises, which measured how aroused they became, it seemed that the students were aroused equally, even though most of them denied that they would be aroused by nonconsensual sex.

I don't think many men reading this election be particularly surprised by that finding. We'll all have experienced situations where we perhaps would have preferred not to become aroused: the reality is that male sexual desire is not entirely under the control of human men, although of course its expression or otherwise is entirely under our control.

Taken from this point of view, what seems remarkable is not that there are so much sexual violence in the world, but that there is not actually even more than there is (although it's possible that such things are massively underreported anyway). To suggest that all men are potential rapists maybe true, but it does a gross disservice to both men and women like, and it's actually quite disrespectful of men. We are governed by our genes, and both men and women alike may find they do not always have the freedom of action they would like to. And of course, how you act in many situations depends on how high level of consciousness and awareness is.

Of course the point is that experiments like the one described above don't establish the kind of link between arousal and behaviour. And if you think about it a bit further, is not even clear from the brief report of the experiment are given above what it is that men actually find arousing: is it the violence, or the sexual act, or the sign of another aroused male, or something else entirely?

Testosterone has been blamed for many things, and it can certainly be hard for women to understand just how powerful its effects on the male body and mind can be. Andrew Sullivan, who once edited the New Republic magazine, and the experience of taking testosterone shots. He claimed that this made him behave very differently: to cut a long story short, he suggested that testosterone made men behave with more aggression, more self-confidence, with more risk-taking, with a degree of physical intimidation and tendency to violence… Presumably also, the more testosterone a man had the more he would demonstrate these behaviors. The problem however is that testosterone doesn't actually do these things: an testosterone does is to accentuate tendencies that are already present in a man.

So, rather than making a man more violent, they facilitate the expression of violence in a man who has that tendency anyway. And while that sounds rather defensive, that is to say, defensive of men in general, it has been very well proven that testosterone merely facilitates the expression of latent behavior. One thing that is interesting is the fact that men with high levels of testosterone are generally found to be the ones who remain active well into their 60s - senior CEOs, for example, are almost always "high testosterone" men.

A number of other experiments have been conducted over the years with the intention of trying to establish just what influence testosterone has on male behaviour. The problem is that these experiments have produced conflicting answers. Professor James M. Dabbs of Georgia University has conducted many experiments in the field and has made some generalizations. For example, men who are physically imposing, highly competitive and have we would describe as an "macho" appearance and attitude do indeed generally have higher levels of testosterone. There is however no link between testosterone levels and criminal behavior. Studies have not demonstrated a correlation between men's level of testosterone and their tendency to rape or commit other sexual crimes. Interestingly enough however, if you take the analysis a stage further, it seems that men who live in a violent environment where aggression and interpersonal conflict are rife, develop higher levels of testosterone. This begins to offer some insight into the possibility that cause-and-effect may not be as simple as we would sometimes believe.

In fact, according to Professor Robert M. Sapolsky, of Stanford University, the reality is actually the testosterone rises in response to aggressive behavior. It's certainly true that competitive sportsman who win a match experience a surge in testosterone after the victory – and it's facts like this would give us some insight into the subtlety of male sexual biology.

Nevertheless, having said all that, testosterone is clearly at the root of all maleness and all masculinity. Without testosterone, the fetus grows into a female, both in body structure and brain structure. Parents of boys and girls will observe that this distinction is clearly obvious in the way that boys and girls behave, and even if you allow for the socialization of children as males or females, the inevitable fact remains that boys are different girls, and the most likely cause of this difference is the influence of testosterone in the developing fetus. Most obviously of course, testosterone is responsible the development of the penis, the very symbol of masculinity, and the organ of the body which is at the centre of male sexual expression and behavior.

There is absolutely no chance of the fetus becoming male, even if it has an XY sex chromosome pair, if there is something wrong with its testosterone producing ability – and that includes the influence of female hormones which are becoming more and more prevalent in the environment for all kinds of reasons, not least because the contraceptive pill is flushed into the sewage system via women's urine.

There's a condition called testicular feminization in which the male fetus lacks any sensitivity in his tissues to the influence of testosterone. This means that every part of the body develops as a female phenotype, although usually the ovaries are not produced and the vagina is short and blind. These individuals are extremely feminine in appearance, and the genetic mutation responsible for this condition is usually only discovered when the child does not menstruate at puberty. There are other degrees of testosterone insensitivity which range on a scale from 1 to 7, and produce conditions such as intersex children, mild hypospadias, and limited masculinity.

In the normal course of events, a baby with XY chromosomes will develop testes and a normal penis and all the internal male sexual organs associated with them. What's very interesting is the subjective experience of the transition from child to adolescent male with sexual desire. For those with high levels of testosterone the sudden onset of intense sexual urges and the frequent penile erections which ensue – whether desired or not – must be so challenging to deal with, and it's at this at this age more than any other, I think, where a boy needs the guidance of older males to learn how to control the testosterone which suddenly flows so potently through his system. This is the testosterone that fuels the self-destructive and risk-taking antics of adolescent males, and it needs to be controlled in a safe way by older men who know how to initiate adolescent males into manhood. Such processes no longer exist in our society, but there are modern male initiation rites which emulate men's initiation rituals of former times. These opportunities forb personal growth for men are vital to the health of today's society.

And as every man over 40 or 50 knows, the net level of testosterone in his system declines with age, partly because his testicles become less efficient at producing it, and partly because his liver becomes less effective at removing estradiol from his system. (This is a variation of oestrogen produced in a man's body which competes with testosterone for the cellular receptors that cause testosterone to be biologically active.) The consequence of this is a whole variety of symptoms known as the andropause: fatigue, muscle pain and ache, depression, lack of motivation, reduce sex drive, and even impotence.