Still, admittedly, at a low level, but now the intelligence is capable, at least, of locating or identifying a nutrient and ingesting it. Organic evolution has begun. And pretty soon there are organisms who have taken the next leap in intelligence. Now that is actually quite a sophisticated computation. It was a messy system.
Bit hit and miss, but essentially the design was achieved by accident.
One of the original organisms was a bit odd and had this tendency to eat anything it could get its pseudopods around, including its siblings. Remarkably, it thrived and divided into many others like itself, who all thrived and so on. And so on. We can even identify major development stages in intelligence, all of which, initially at least, must have conferred significant survival advantages over the first members of a species to adopt them. Possibly the next step was the first level of co-operation.