The eagle, so I've read, is one of the creatures with the best sight in the animal kingdom. It can see eight times as far as a human and has telephoto eyes so it can zoom in on its prey.
It is these animals that a lot of product manufacturers write their instructions for. I have no idea why. I've never seen an eagle assembling a bookcase, microwaving a curry or taking headache pills.
With a computer screen at what you might call 'standard' distance, I can read down to about a 10px font without spectacles. I require my reading glasses for 8px or 9px and a magnifying glass for anything below 8px.
I would make any font below 10px illegal. Use a font below 8px and you'll spend life in prison with hard labour and a viscous beating every Tuesday. It's not just the font size that matters, though. The kerning and line spacing can also have a big impact.
With a computer, I can zoom things of course, but I do not have that luxury with the paper instructions that come with a lot of products. I either need a magnifying glass or I just guess what they say.
I have rules. If I can't read the instructions on a box of pills, I take two of them because that seems to be a safe and effective dose of most things. If I can't read the instructions on a microwave meal, I cook it for three and a half minutes. If I can't read the instructions on a bookcase, I randomly screw and hammer things together until I end up up with something that only vaguely resembles a bookcase, but could possibly be a tree-house.
If I have to read the warnings on a box of pills in an emergency, it's safe to say I'll die. As it happens, I don't particularly recommend reading the instructions that come with pills. If you read the possible side-effects you'd never take the pills in the first place. There are always pages of them, suggesting you might suffer from anything ranging from a mild headache to terrible, painful death.
I'm told there's an obesity crisis in the UK and we're encouraged to eat carefully. It's impossible, though, because nobody can read the subatomic font on the back of a packet of food.
So my plea to manufacturers is this: write the fucking instructions in a font that humans can read.