The most common question people ask about depression is 'How do you know the difference between depression and just feeling sad?'. What marks me and all the others who suffer from depression out from people who are just down in the dumps, feeling the weight of the world or having a bit of a crap day?
It's an interesting question, not least because it's one that doctors have to deal with on a daily basis. The methods for identifying who is suffering from depression and who isn't are far from perfect. The most common diagnostic tool I've encountered takes the form of a questionnaire. It asks around ten questions about your emotional and physical state, spanning from energy levels, to eating habits, to suicidal thoughts, and you answer based on how often you've had those symptoms over the past two weeks - not at all, some days, most days, or nearly every day.
This approach encounters two problems: the way it takes a snapshot of the last two weeks and doesn't take account of individual days or times, and the fact that it doesn't examine the severity of symptoms. Doctors tend to get around this by asking how much your symptoms are affecting you: if I tell them that I've wanted to kill myself, they ask whether I've self-harmed (yes), whether I've made any plans (uhhh, kind of?) and whether I've acted on them (does plaiting a bunch of ties together to make a pretty noose count?).
This clinical approach doesn't quite get to the heart of the issue. It tries to put an objective lens over something that is necessarily subjective. If you go to hospital and they come round and poke and prod and squeeze and ask 'does that hurt?' and you say 'no, no, no... gah, bloody hell, yes', and then they ask 'on a scale of one to ten how much does it hurt?' and you think 'if I try to say a random number I'm just going to say 'seven', because everyone says seven when it's a random number', so you subsequently decide to figure it out properly. So you attempt to put a label on what one is and what ten is. You decide that one is probably sitting on a deckchair on a hot summer's day and feeling vague discomfort as the sun begins to roast your back and you realise that you're going to be spending the next two weeks as a walking crustacean. You then decide that ten is most likely stepping on an upturned plug whilst simultaneously catching your testicles/lady-parts in the zip of your jeans, receiving a paper cut on your eyelid, being punched in the solar plexus, having your nose hairs pulled out and being hit by an articulated lorry. On this scale, your pain is a five, the equivalent of having a cat knead its claws on your back as you are forced to listen to Rick Astley's greatest hits on repeat.
If we can't even put our finger on physical pain (because it's too tender), how can we possibly hope to quantify mental pain? Trying to put on a scale from one to ten how much you want to hurt yourself is not only about as feasible as fitting so many camels through so many needles, but it also attempts to strip all of the emotion from a disorder which is intrinsically emotional. I may not have considered self-harm in the last two weeks, but that betrays nothing of my emotional state. There are all kinds of factors which might mean that I feel like a child who's just dropped their ice cream in the sand without resorting to cutting. I might feel that self-harming is attention seeking (it's not), that cutting is for people who have 'real depression' and not for people like me, or that it's just not the kind of mental pain that taking a razor blade to my wrists is going to alleviate.
There is no scale for emotional pain and distress, nothing that we can use to say that one person is objectively suffering more than any other. This is part of what makes differentiating between depression and plain sadness so difficult. One school of thought is that everyone's problems take up the same amount of room in their own heads, it's just that some of us aren't as capable of dealing with those problems. I find this a constructive way to think about the issue. It deals with the common problem that people feel unjustified in claiming that they are suffering from depression because their problems are objectively less bad than another person's. It's very easy to attempt to classify our emotional issues based on the scale of problems that we face, from being late to a lecture, through having inspired the wrath of our significant other, up to dealing with friends who are suffering from stress, topping out with bereavement. On this scale, it feels unreasonable to say that whilst my friend is coping extremely well with the recent death of their mother, I'm suffering from depression and it's been triggered off this time because a girl I like didn't reply to a text.
If we instead say that there is no universal, objective measure for mental pain, that legitimises people who feel that they may have depression and eradicates a lot of the 'snap out of it' stigma that permeates narratives of mental illness. This leaves us with the original question: how do you know when what you're feeling is depression?
I think there are three main indicators: time, depth and triggers. First, time. Whilst for most people sadness tends to come and go within reasonable limits, what delineates depression is that it lasts longer than it should. Crying into a tub of Phish Food for two days whilst watching Bridget Jones on repeat is perfectly reasonable. Finding yourself incapable of getting out of bed in the morning to the point where you're missing classes, meetings and life because you think there's a slim chance that you may have upset one of your friends with a passing remark is not. This links in to depth: the degree to which we are sad tends to be proportional to the severity of a problem. Notwithstanding the prior argument that everyone's problems take up the same amount of room in their heads, a hallmark of depression is that the response to any given negative situation is disproportionate. There is no possible world in which it is ok to spend the majority of the day in bed, fighting a biased jury in your mind, just because you haven't been able to do the laundry or go to the gym for a while.
Third, and for me most importantly, there's the issue of triggers. Emotions aren't rational, but they should have a reason. Often in depression there's no reason for the way you're feeling. It might be that there's something which has set it off, but sometimes there just isn't. Your friends and family ask you what's wrong, why you're feeling this way, what they can do to help, and the answer to all three questions is 'I don't know'. There doesn't appear to be any rhyme or reason to it. Some days you're floating along quite happily, being really good at doing this living thing, when apropos of nothing you're picked up like a rag doll and shaken, and you don't know who's picked you up and you don't know why they're shaking you or when they're going to put you down or even if they're going to put you down. You just know that you're being shaken, and it's awful, and you would do anything for it to stop but it just won't stop. You wonder to yourself whether maybe this is it, this is the time it doesn't stop and you keep being shaken about until it's too much and you make yourself a little rag doll noose and end your little rag doll life. It feels like it's never going to stop, they're never going to put you down again, and you can't think or feel anything but pain, and it hurts all over and you're stuck in bed and immobile but on the inside it's like your entire mind is made of barbed wire and every single mental move you make rips open another gash in your already torn-up body.
And then it stops. You're dropped bodily onto the ground, and you feel like maybe living life is tenable again. It's such a wonderful relief that it merits opening an entire paragraph with a connective, and you look back on that whole period you were being shaken and wonder what on earth all the fuss was about. Surely it can't have been that bad? Five minutes into living again, you can't remember why you were sad, and you can't imagine it happening again any time soon. You go on your merry way, your myopia for the past the only thing preventing you from looking back and going truly insane. Then, when you least expect it (because it's always when you least expect it), it happens again, maybe for a reason this time.
But it's never completely gone. Even when you're living a normal life, pretending to be a functioning human being who can Deal With Things, there's this sheen over everything which takes away all of the world's gloss. It's like all the colours are just that little bit attenuated and you can never feel quite as much as the next person. I don't know, maybe this is the drugs, but sometimes it's worse than the episodes themselves. Sometimes you would give anything just to be able to feel the same enthusiasm for life that you used to have in spades.
This, in brief, is what it's like to suffer from depression. Because it's an illness which takes place primarily in the mind everyone's experiences are different, but I think that at least some of what I've described here will be common to a lot of people who have it. The way that the symptoms of depression are longer and deeper than any given sadness and the way that they often defy reason is what marks them out as pathological. Fundamentally, the main way you can tell that you might be depressed is when all these negative emotions are interfering with your daily functioning, making it difficult to live your life the way you feel you should be able to. If you ever feel that way, get help. Just do it. Don't tell yourself to man up or woman up or snap out of it. Nobody need suffer alone. There is help out there, go and get it.