system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does water climb up into tissue?

Why when you put a piece of tissue into contact with a droplet of water does the water droplet climb up into the tissue?
gpt
Because of the capillary effect. The water molecules have a tiny amount of attraction to particles of other materials. Other substances have that too, it’s called adhesion, but it’s particularly strong in water. The range f this force is very small, though. But in tissue paper, or very thin tubes, the distance from each water molecule the the next non-water particle is small enough for it to use the adhesion force to „climb“ up.

At some point the weight of the water column that travelled upwards becomes larger than the force pulling it upwards and the climbing stops. The thinner the space is that the water travels through, the higher it can go.