system
Given the following post, respond as if you're commenting on Reddit:
human
Given enough time could a crab, snail or anything really eventually evolve to become as intelligent as us?

EDIT: Ok wow lots of responses. Its going to take a while to read through them all but I think the top comments and most others describe it well. 

It isn't just time, its environmental factors as well.
gpt
As long as increased intelligence was competitively advantageous from a fitness perspective, the rest of evolution is up to random mutation.

In a hypothetically infinite time scale, mutations that increase crustacean intelligence certainly could accumulate.

However, it's also important to keep in mind that "intelligence" is not some sort of evolutionarily apex quality. Most living things are quite well adapted to their environments already and face a cross-section of different selective pressures than early hominids. Optimizing energy balance, disease resistance, evasion of or defense against predators, ability to attract mates and beget fit progeny, exploiting new ecological niches, etc are all extremely powerful forces that *may* improve with increased intelligence, but are largely unrelated.

In addition, any intelligence needs to be utilizeable in order to be a benefit. If we consider "tool use" as a marker of intelligence... that would be incredibly challenging for a creature with the body pattern of a snail. Higher order brains are energetically very expensive, and they need to be worth it.