Shrinks by Jeffrey A Lieberman, book review: We're still in the dark ages when it comes to mental health

Reading Jeffrey Lieberman's Shrinks: The Untold Story of Psychiatry, we are given a microscope to this most recent chapter of mental health care.

The author clearly believes we have come a long way from Ancient Greece. While he recognises psychiatry has had its unpleasant problems in the past (gruesome lobotomies and electroconvulsive therapy, for example) his is a rather positive and evangelical account. Even electroconvulsive therapy, he suggests, can be used for good.

My reservation is to this optimistic idea that we have now reached some special point in history where, after the undeniable misery of the past, we now have the right solutions. Or at least, some of them. "For the first time in its long and notorious history, psychiatry can offer scientific, humane and effective treatments."

Our instinct is always to want to believe that we have reached the point in which we have the answers, but there have been many, many people throughout history who have believed they had the answers, and with dangerous consequences.

There is still so much we don't know about the human brain. Fifty years ago we were told mental illness was a matter of brain chemistry. This idea has become a very strong one, not least because a whole industry has grown out of the belief that simply by readjusting our chemical balance and adjusting neurotransmitters such as serotonin and dopamine we can make everything all right.

The truth is that even this idea is shaky. Measuring, say, serotonin levels in an active living human brain is a tricky thing to do. An unfortunate by-product is that most scientific research into the benefits of pharmaceuticals is being done by companies selling pharmaceuticals.

When I came to research my memoir of depression, I imagined that the answers were all there but that I hadn't come across them. The horrible truth, when it comes to mental illness, is that we are still in the dark ages. As Scull puts it "the metaphysical wager that much of Western medicine embraced centuries ago, that madness had its roots in the body, has in most respects yet to pay off."

So, in the meantime, we must acknowledge what we don't know and what we are uncertain about. Yes, as both these books show, we have made some steps. We have gone from a generally religious approach toward mental illness to a generally scientific one, but we must always be careful that we don't get too religious about our science. We must never have blind faith in anything – pills, talk therapy, exercise, diet, and certainly ECT – where doubt remains.

We need to embrace our doubt. That is not to say that we should be defeatist, or imagine that the mentally unwell cannot get better. It is just to say that our language around mental health has changed a lot faster than the results. People do get better. We can and we do and we have. We just need to be aware of our place somewhere right in the middle of the history of mental illness, and both these books help us understand that place a little better. For that, at least, we should be thankful.

Matt Haig's memoir Reasons to Stay Alive (Canongate, £9.99) is out now