Any unintelligent being can become fully sapient if it lives long enough.
Formerly Instant Sapience, Just Add Time In Real Life, there are limits to how intelligent something is. Things like how easily it learns, how much information it can "remember", and whether or not it's able to use this information in a useful way. Not so in the world of fiction. Nope, just give a robot, animal, or whatnot a few hundred years or so and they'll learn enough to gain a human-level intelligence. Robots are able to program themselves to do tasks that would be otherwise impossible, animals walk around on two legs and speak like people, and the computer has taught itself to speak fluent French... and consequently, to love! In other words, this is when a normally non-sapient being gains an incredible amount of intelligence over time by somehow remembering everything it has ever "learned" over the years, and gaining the ability to reason from it. Needless to say this usually take a lot of time, and may require that the being in question possess or gain some form of Immortality as a pre-requisite. Contrast Instant A.I., Just Add Water, where a robot or AI immediately gains intelligence through improbable means, like a bolt of lightning. This trope has crossover potential with It Came from the Fridge, which results in a mold or microbe colony being in the fridge so long it gains the capability of speech, solving mathematical equations, or sending diplomats for rent negotiation. This isn't something applied to planets (as in David Brin's Uplift series, where planets are allowed to lie fallow until sentience life forms arise). Note: This trope name uses Sapience rather than Sentience because Sapience, or wisdown, is the ability to reason, whereas Sentience is the ability to experience emotion. Generally, the beings that benefit from this trope all start out as sentient and gain sapience much later because of it.
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